I'm a .NET developer trying to make the leap into objective-c iPhone programming. I created my first app - just a simple portfolio with multiple xibs.
I've just come across MonoTouch which lets you develop iPhone apps in C# or .NET. Has anyone tried this out? I'd be interested to know people opinions on it.
I have been using it for 5 months now, and I have an app developed using it in the App Store ( http://escoz.com/quicklytics ), as well as a few internal projects deployed at a client.
Here's my point of view:
If you're a .NET developer, and want to develop for the iPhone, you'll need to learn two new things: Obj-C and the iPhone SDK. Both things are quite different from .NET, and it can be quite difficult to get going, specially if you have a deadline. In general, you'll end up getting stuff done, but mostly by copying-pasting a lot of random code from the web for months and months. Yeah, you may actually spend the time and learn it properly and not do that, but that will take a lot of time.
Using MonoTouch allows you to totally skip the first problem (obj-c) and helps tremendously with the second (sdk). After a couple of days reading and watching videos online you can already be fairly productive, using things you're familiar.
Yeah, it does cost at least $400.00, and if you're thinking about developing stuff for fun over the weekend, that may be a little expensive, but if you're thinking about writing code for work, this is a no brainer.. The amount of time that it'll save costs a lot more than the $400.00.
Size of apps: the apps will be larger (6-7Mb larger in average): nobody cares about it, honestly.
Speed: while technically it is possible to make obj-c apps that run a little faster than C#, in practice that simply doesn't happen: monotouch is as fast as obj-c for all purposes.
Bugs: not having to deal with memory leaks all the time and having a higher language to develop in is a huge deal.
Even if in the end you want to pick up Obj-C, I would highly recommend you start with MonoTouch and get familiar with the APIs. The demo is available for free and allows you to do everything other than deploying to an iPhone. Only when you know how the API works move to Obj-C (if you still want to do it at the end).
One last point: if you're thinking about porting your apps to other mobile platforms, MonoTouch seems to be the platform to use right now: most of your code can be ported to the Windows Phone SDK, and Apple will release MonoDroid (MonoTouch for Android) in the next 5-6 months.. This really matters to me, maybe it also matters to you.
Tried it, loved it.
Being able to re-use .NET knowledge is a definite plus (even though learning Obj-C is most definitely still encouraged.
The only downside is that the executables are larger than their respective Obj-C counterparts. That...and the cost associated with the license (if you're going to distribute your apps).
I tried it.
If you think you're going to program many programs for iPhone, I think is better to learn Objective-C. But, if you have some big source code or existing programs written in C#, that MonoTouch may be the best solution for you!
Rory Blyth addresses this very point in a very similar question:
Monotouch or Titanium for rapid application development on IPhone?
Our whole dev shop moved from XCode and Objective-C to MonoTouch. Most of the team also have .NET C# skills.
We're about 2/3 more productive in our XMl/database-centric apps + web services . Monotouch has a lot of built in tools for those things.
It's quite expensive, and you still need a Mac.. so if your idea was to stay in Windows and write iPhone apps using Visual Studio, you're out of luck sorry... At $399 as the lowest price, on top of the $99 for a developer license from Apple, I don't think it's worth it unless someone else is paying (eg, a corporation etc). You'd be better off sticking with Objective-C and Xcode, since you've already played with it.
Related
Titanium claims it can do the same app on average 70% faster than native XCode.
What's been everyone else's experience in terms of difference in speed of development （between native XCode and PhoneGap or titanium) ?
Let's say an app like Kik Messenger or Badoo ....
Typically, a good XCode developer can do it in 4-5 weeks, assuming graphics and backend are in place.
What would it take for an experienced Titanium (HTML5) person to achieve this? (roughly)
Time to market depends on quality of specifications, process and people, much more than the underlying technology or framework.
Coding a real application with Appcelerator Titanium is not that easy, and runtime performances are SLOWER than native code because it's using a javascript engine as a bridge. Especially with a big TableView, it's much more slower, and the feeling is just not the same. But once you have purged the memory leaks, the feeling is nevertheless incredibly better than with HTML5.
You should be interested in Titanium or PhoneGap(now known as Cordova) if you plan to distribute your application on other devices or if you really don't like Objective C.
If not, keep it with the Native Xcode.
I would add that Cordova will not make any UI, but let you access camera, accelerometer or GPS with javascript inside HTML5 code. You would probably use Sencha Touch or jqueryMobile with Cordova.
In my experience, if the app is not a simple template app then you would be better advised to create a native app for each platform.
As Rob says, trying to overcome the lowest-common denominator situation and overcoming limitations in cross-platform "solutions" usually means it takes longer to code than doing it natively in the first place.
You might even hit a problem which causes you to abandon ship and start from scratch as native apps. So if you decide to go a PhoneGap or Titanium route then make sure you research fully before starting and that you won't have future requirements not covered by them.
If you are an iOS developer and you are developing it only for iOS device, then it is better to code using XCode. If you are more into Javascript and developing for both android and iOS then you should use Titanium or Phonegap. Between Titanium and Phonegap, I found it easier to code using Titanium(and yes fast as well). But I am not sure how much worth is using Titanium. http://usingimho.wordpress.com/2011/06/14/why-you-should-stay-away-from-appcelerators-titanium/
I'm actually performing a fairly intensive survey of all the major cross-platform mobile development kits right now. I started by making a sample application from scratch in IOS that uses a few simple device features, and then reimplemented that as an Adroid app. Both of those took about a day to complete (the android took maybe half a day longer). Since I've never written an android app before, I think that's a good baseline in terms of comparing development time between the various other frameworks I'm testing out.
I'll update this comment in a few weeks with a blog post when I'm done, but for the moment I've been finding that these cross-platform kits are vastly more difficult to use and take a lot more time, even for the simplest applications. and despite this, there's still quite a bit of custom per-device code that has to be written for UI and fundamental idiosyncratic differences between how device services function, so you don't really get the value of a true "single code base" that you may have been expecting.
I think the main value in these may turn out not to be anything related to development time or code reuse, but instead only as a way for non-app-developers to create simple prototypes that can later be handed over to the "real" mobile developers to be built out into true native apps afterwards... Not really all that useful in my opinion, but maybe my thoughts will change as I delve into this further.
Appcelerator is not HTML5, it is a native app built in a higher level language of JavaScript. It abstracts the complexity of common elements away and provides huge value, ping me offline to know more. I run our California business.
if mono touch is available than why we should use mac environment(sdk,xcode+Interface Builder)?
what are the disadvantage of monotouch compare to xcode?
I always prefer working in the language that is most philosophically aligned with the platform I am developing for.
That is to say, the frameworks the whole platform is built around were written for and in Objective-C. As such, if you are working in Objective-C yourself for a while you understand why things are built the way they are, and can also anticipate calls that might exist or behaviors.
Just as I would not develop for Windows Phone 7 in anything but Silverlight, I would not program the iPhone in anything but Objective-C in order to get the most out of the platform. New language? That's a benefit as people should learn new languages now and then anyway. And it's not like it saves you that much time to use a language you already know since a large majority of your time will be spent learning the frameworks (which MonoTouch lets you call into).
I feel like this needs an answer from the MT camp, too.
Why eat fish, if you can have meat? Why speak German, if English is understood? Why watch CNN if there is FOX? Why vote vote for the Republicans if there are the Democrats? Why...? And so on.
It is your choice! If you have worked with C# for a long time and want to have quick results on iOS, go MonoTouch. Especially if you have a collection of APIs or methods you can reuse, MT is the way to go. If you want to learn a new language (ObjC), go for it. Even if you use MT in the end, knowing ObjC is somehow crucial because it helps you understand why things work as they do.
Hello here is my personal opinion,
I've also been on .Net world for a while, when iPhone launched the ability to create native apps, it called my whole attention and i really tried to learn objc, i took 2 books and started trying and trying and trying like for a month and then I left iPHone programming due to you had to make tons of things than on .NET was a line away for example the GC.
When Miguel de Icaza launched MonoTouch i gave it a try and i realized that most of my previously done code was fully funcional (i've always tried to separate ui code from business code) and this is really the point of .NET on the iPhone, to bring most of your already done business logic to the device.
Also on objc you wont find anything like LINQ or var keyword, consuming web services on MonoTouch its just a few clicks away etc.
If you want to target the Android platform there is also MonoDroid (monodroid.net) wich its coming out later this year the stable release, you can give it a try right now on the beta state. Also if you want to target Mac OSX there is MonoMac. So you can share class libs between all this 3 platforms (also al mono/.net supported ones) without hassle not to mention it will work on windows too and viceversa (when possible) (Also dont forget about WP7).
The only thing you will need to worry about its the UI but most of your business logic should work. here is a complete list of .NET Assemblies supported in MonoTouch http://monotouch.net/Documentation/Assemblies and also MonoTouch exposes a C#/CIL binding to all the CocoaTouch APIs.
Also the support of the MonoTouch team is awesome you can just get on IRC ans ask a question and it will be answered right away, mailing list too :)
I really enjoy MonoTouch, i know that no language is perfect for all tasks, and Objective-C is no exception.
Every example, tutorial, and piece of documentation will be written in Objective-C, and mono will just be calling into Objective-C code under the hood. If you really feel like C# is worth mentally translating everything, and adding an extra layer in your code, go for it I guess.
As a C# developer, I've found Objective-C to be horribly painful to become confident with. It's taken about two months, and two excellent resources to get to this stage.
Get your Visa card out, you'll need to spend a total of $54.
1. The free Stanford "Developing apps for iOS" lectures.
Pure brilliance, and it makes learning Objective-C very clear.
http://itunes.apple.com/us/itunes-u/developing-apps-for-ios-sd/id395631522
2. The iOS Apprentice series.
This is where you'll need to cough up the $54. It teaches you, step by step, how to program in Objective-C, and the apps you build are actually pretty impressive. Part 1 (of the 4 parts) is completely free, so you can give it a go before parting with any cash.
http://www.raywenderlich.com/store/ios-apprentice
I've yet to find any iOS books which match the clarity and friendliness of these two resources.
Finally, don't buy any books unless they specifically say that they're for iOS5 and XCode 4. This latest version of XCode is simply too different to make them useful.
Disclaimer: I don't work for any of the resources mentioned in this thread !
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I want to build a mobile/tablet application whose core feature will be taking pictures with the camera , viewing pictures and receiving notifications. Also I want to target iphone, ipad and android platforms.
Titanium appcelerator piqued my interest because of its cross platform appeal. However I am concerned because I've read mixed reviews on SO and other sites. The things that worry me are:
Subpar android support
Camera support not fully capable (e.g ios 4.1 HDR capability)
Camera support buggy
The nightmare scenario for me would be to invest time in titanium only to discover later on that its a major PITA and drop it and go "native"
Please share your thoughts and experiences.
I chose Titanium for a serious application, although one that does not use the camera. I think there are a variety of things that could play into your decision...
If your app intends to do "fancy" stuff with the camera, or some real heavy image processing and so on, you're likely better off going native. If on the other hand, you just want to have it take pictures, and then those will be used as-is, or sent to a server, or what not, then Titanium should work just fine. Titanium does have some processing and image manipulation things, but as others have said, if you really want to take advantage of the device's hardware, you probably want to go full native.
It should also be noted, and Appcelerator says this as well, that with a Titanium app, you won't just write a single app that works as-is on all devices. You will need to taylor the UI to each device (or class of device, i.e. iPhone, Android), because they have different UI's, and different standard UI flows and so on.
But, one of the potential advantages to Titanium is if you don't know Objective-C and/or Java, and you do know JavaScript (and in my case, I'm actually using Coffeescript :). Or, if you would enjoy your work much more writing JS than ObjC/Java. This was one of the main reasons for me. I have done some ObjC dev in the past, and don't even mind it, but this project I'm doing is on a very very aggressive schedule, and it was just going to be far more effective for me to use Titanium. I was able to get set up and build an app extremely quickly, and I am not spending any time having to become more deeply familiar with the programming language I'm using, memory management bits (you can't fully ignore this with Titanium, but essentially they're doing it for you). Based on the folks I've talked to, and how much time they spend with memory management, Interface Builder issues (this is mostly the ease of forgetting to setup connections or hook various things up, IB is actually a pretty great tool), and so on, I'm quite glad I'm using Titanium.
While I expect to do an Android version at some point, it's not a priority. But, I'm glad to know that a large chunk of my app code will be re-usable, tested, etc. and that I'll wind up mostly just building/revamping the UI for Android, not rewriting networking code, data management, and so on. Android support will be much better (supposedly) in Titanium 1.5, but you may want to wait for that release to evaluate Android if that's a priority.
Finally, Titanium does have a "module" system, that allows you to wrap native code, exposing it as a JavaScript interface in Titanium. We are about to leverage this to integrate a third party library, and at least for what we need, it looks very easy to use, and has given me a little more confidence that if some particular native feature we need access to comes up, that we'd have a decent chance of integrating that while still using Titanium, but I think it would depend on what the particular native functionality was.
Good luck and enjoy building a mobile app, it's pretty fun!
We have been using Titanium in one of our projects for around 2 months, and frankly speaking our experience with Titanium is too bad.
As per my opinion, below are some major drawbacks of Titanium:
1) First thing is you will not get debugging support at all (We can understand how debugging require in any of the project and in any of the technologies).
2) Titanium is NOT fully supporting all the features of Android/iPhone; beyond some level it will not give you support.
3) Comparing with Android/iPhone SDK, developers will get very less amount of help from the internet and API library (Titanium provides the API library help file).
These are the general issues that end developers face while dealing with Titanium and I suppose sometimes it will be tedious and frustrating work for them.
If the functionality of your application is somewhat like displaying data from the web (like many news, media type apps) then Titanium is the suitable option; otherwise not.
The Android support is not near as good as it is for the iPhone. If you were to just say iPhone I would say you would have luck using Titanium. However, I think trying to build one code base in Appcelerator and also use in your Android environment may not be the best experience.
That said, IMO doing Android / Java code is much easier than doing Objective C / iPhone work.
So worst case I would consider using Titanium for your iPhone version & do Android in Java.
You can give it a shot doing them both in Titanium, but worst case code the Java version.
I just hate objective C and the 'native' Apple development environment so much.
I would recommend against using a cross-platform toolkit when interacting with device hardware is one of the key requirements of your application. I haven't worked with Titanium before, but I find it hard to believe that they will give you the same level of hardware access that you get with native frameworks.
In particular, iOS 4.0 added a mess of new capabilities regarding the camera, including live video frame processing through AVFoundation, and I find it hard to believe that a third-party framework will keep up as these platforms advance. To be honest, it's pretty easy to write an application that interacts with the camera on the iPhone nowadays (count the number of them on the App Store as an indicator of this). I wrote a live camera frame processing application in about six hours the other day.
I can't speak for Android, but I imagine dealing with cameras is fairly trivial using the native APIs there as well.
You're also going to find performance testing and debugging your application to be far easier using the native tools than those supplied through a third party. In particular, Apple's Instruments is an extremely powerful, yet easy to work with, application for tracking down CPU and memory issues within your application.
There's also the community aspect. You'll find far, far more people working on Android and Cocoa Touch than on Titanium (just look at the numbers of questions in the various tags on Stack Overflow to see that). This means many more tutorials and a whole lot more sample code that you can use.
The time you'll spend getting your iPhone and Android build environments set up, and submitting to both stores, will be the same no matter if you go with a native environment or with Titanium.
In the end, even with learning both platforms, I think you'll come out ahead by avoiding a cross-platform solution. Trust me, I've tried to do cross-platform development before for other projects and ended up with lowest-common-denominator products that took much longer to write.
I've developed an Appcelerator-based camera application and was very pleased with it. I think some of the negative reviews come from the fact that it's a bit hard to get set up (more due to Apple's crazy developer registration process).
Once I got started, it was easy to do things like overlays on top of the camera screen. I was really expecting difficulty with that part, but it worked well.
I have spoken with the Appcelerator team in the past, and they are a great group to work with. I've seen them be responsive to other user issues, and I'd trust that if I ran across a real bug, they would address it quickly.
A little late, but my two cents...
I honestly believe you can very quickly prototype an application with Titanium Appcelerator and focus on the critical feature sets to determine if it is the appropriate tool for you.
All developers have there opinions and experience(s) which influence there comments; developers have different ways of learning and different levels of productivity... In the end, it comes down to how are you most productive with the tools available to you.
Since you are stating from the start that you want to deliver a solution an multiple platforms, I think it would be a poor decision on your part to not even spend a week or two investigating cross-platform frameworks and then making the decision based on your personal experience.
There is Titanium Appcelerator and there is also PhoneGap, where PhoneGap might help you is that there is the ability to extend/enhance the underlying framework through writing plugins (I wrote one for iphone ) and there is an android one on my blog also... this can fill missing gaps for you when you move across platforms.
Also since the UI in a phone gap solution is HTML5 Webkit based, it can give you a consistent look and feel across you devices if you like. Frameworks like jQTouch and JQuery Mobile are being used for UX with PhoneGap Application
I reviewed negative feedback for Titanium Appcelerator but I tottaly agree with Aaron Saunders that if you use PhongeGap Development is support HTML5 which can getting easy to make apps for iPhone, iPad and Android mobile.
Has anyone highlighted the cost off titanium.
I was contacted by them today and if you are more than a one man band you have to sign up for a partnership program else you are held liable for breech of contract if you release the app.
The partnership program is £5000 which is far to much for us as a start up company when it's our first application, we are currently looking for a different option now.
I'm new to IPhone development and have to decide on a suitable tool to develop my application in. Since I am know C# / .NET, but not objective C, Mono Touch seems appealing to me. But is it is worth spending the extra $400?
If have tried both, I'd be interested in your opinion.
I just posted about this at www.zouak.com, but in short for me it was a case of divide and conquer. I have years of .NET experience and honestly found learning Objective-C frustrating. Having a new language plus a new set of tools reduced my productivity significantly, also having to deal with manual memory management after years of not (prior to 2001 when I started with .NET I was a Java guy since its inception, so it's been a while) was an extra layer of "been there, don't want to go back."
I've found the MonoTouch toolkit to be very worthwhile, and while I understand some of the objections and concerns, I'm someone for whom leveraging what I know (C#) allowed me to focus on what I didn't know (Interface Builder, the API, etc.). At this point now that I've built up a significant amount of familiarity with the Apple tools I'm nearing a point where if I wanted I could look at taking on Objective-C as a new language, given that I am a lot more comfortable, but for me learning a new language isn't as rewarding an accomplishment for me at this point in my career compared with learning a platform and getting quality applications out the door is. For other folks I know they enjoy delivering "as Apple intended", and I fully respect that. Also, if Apple had a Java toolkit, I would be all over that. But the conceptual distance between C# and Objective-C is more than I'm willing to invest at this point.
That's my 2 cents,
Driss.
Great podcast on this week's dotnetrocks about this.
One HUGE factor that would sway me is the fact that they are currently working on Monodroid and I guess that WinMo 7 will probably be supported through some moonlight magic.
Imagine targetting the top 3 mobile platforms with one language? Sweet....
I've been using MonoTouch for 5 months, and really like it.
Take a look at my answer to a similar question here: MonoTouch - has anyone used this?
I am an iPhone developer, I have tried mono touch, but for me I would say NO, it's not worth the extra 400.
First of all several free frameworks exist that allow you to target multiple platforms at once using different (usually high level) languages, such as PhoneGap, there's even a Flex framework somewhere, without counting Unity3D which actually uses C# and even allows you to deploy on iPhone and Nintendo Wii.
Some of the Cons of using this third party frameworks are:
1- Extra software layer, which obviously increases the possibility of failure. Last year it happened with Unity3D. Somehow the applications developed with it started being rejected by Apple (official Unity announcement here) , Unity guys responded fast, and I think they fixed the issue with Apple in 3 days. But what if 3 days is too much for you, or even worse, what if the external framework that you are using to develop doesn't have that quality of support and the 3 days end up being weeks?... what if your applications got broken with an OS update ?
2- You totally loose Xcode debugging chances (loose the symbols), and you are kinda reduced to printf debug. Of course you can debug in the Mono IDE, but still, Xcode is a powerful beast and all the SDK Betas are delivered to the developers to be used with particular Xcode versions.
3- Binary size tends to be bigger in comparison to native Objective-C applications. ( 6 to 7Mb larger in average ), and remember that if your application is above 20 Mb it can't be downloaded from an iPhone using 3G or Edge, ( which is the most popular way to install apps ). So if that matters to you, it's another issue.
In conclusion:
If you want to use MonoTouch because you don't know Objective-C, go for it, but still I would really recommend you to take a bit of time to learn the Objective-C language and the official Apple API's. Here's a great point of view about this.
I would say no, because the biggest thing to learn about the iPhone SDK is not Objective-C, but the APIs instead. Even if you used Mono Touch, you would have to learn the API for the iPhone.
It never hurts to learn a new programming language.
(However, don't listen to me, because I am using Lua to write my iPhone applications...)
As a .NET developer, I always dreamed for the possibility to develop with my existing skills (C#) applications for the iPhone.
Both programs require a Mac and the iPhone SDK installed.
Appcelerator Titanium was the first app I tried, and it is based on exposing some iPhone native api to javascript so that they can be called using that language.
Monotouch starts at $399 for being able to deploy on the iPhone and not on the iPhone simulator while Titanium is free.
Monotouch (Monodevelop) has an IDE that is currently missing in Titanium (but you can use any editor like Textmate, Aptana...)
I think both program generate at the end a native precompiled app (also if I am not sure about the size of the final app on the iPhone as I think the .NET framework calls are prelilnked at compilation time in Monotouch).
I am also not sure about the full coverage of all the iPhone API and features.
Titanium has also the advantage to enable Android app development but as a C# developer I still find Monotouch experience more like the Visual Studio one.
Which one would you choose and what are your experiences on Monotouch and Titanium?
Like any which-tool-or-platform-or-language-or-framework-or-whatever question, it should really come down to what you want.
Forget all the if-you-want-to-develop-for-this-platform-then-you-have-to-pay-your-dues advice. If you're interested in learning Objective-C, Xcode, and associated Apple bits, then go for it. I did. It's been fun, but my interest was in developing iPhone apps. Learning a new language, framework, and IDE was just a bonus (I like this stuff). It was also necessary when I started.
I've been working with MonoTouch since it was released, and I love it. I prefer C# to Objective-C, and I like having access to the subset of the .Net (Mono) framework that MonoTouch provides. There are certain things that are simply easier to do with .Net than Cocoa (string manipulation, date manipulation, anything XML, etc.).
I also like not having to deal with reference-counting anymore. I was spoiled by years of not having to keep track of resources at that level. I don't mind having to clean up after myself, but I don't want to have to manually do something that every other modern dev platform I've used does for me automatically. Plus, even for seasoned Objective-C devs, reference-counting isn't a no-brainer. Scroll through OS X's console output sometime to see how many apps crash due to memory-management issues (I know - this can happen with basically any app, but it's far easier to make the mistakes that lead to this situation when you get overworked devs involved whose attention spans have been destroyed by twelve hours of if this and if that and else this and else that and blah blah blah).
I still use Objective-C/Xcode - I've really learned to like Apple's tools. I honestly feel they're awkward and a bit arcane, but still fun.
But... then I also like this:
public string SomeString { get; set; }
To do the same thing with Objective-C (on the iPhone, anyway) requires that you declare a local variable to back the property, write the property declaration, and then use the "synthesize" directive to have the property generated for you (depending on what property attributes you specify, you might have a property that wraps getters and setters that take care of reference-counting for you - overall, this is a time-saver, but the C# Way is the clear winner here).
That's just one example of how MonoTouch can make your life easier, especially if you're used to .Net/Java/Python/other languages that don't require that you get your fingers dirty with memory-mangement (unless you want to).
As far as iPhone-ness is concerned, aside from brining part of .Net to the iPhone world, the MonoTouch namespace maps to CocoaTouch, so if you're confused about, say, the MonoTouch UIViewController, you can just hop over to Apple's docs on the UIViewController. MonoTouch .Net-izes CocoaTouch, but it's close enough that you're unlikely to hit a wall (that wouldn't have also hit if you were using Xcode/Objective-C). It's slick.
Titanium is different. Since they're trying (trying) to create an abstraction layer that lets you write the same app for multiple platforms, you're going to deal with the usual drawbacks: Totally different APIs, loss of flexibility (the same could be said of MonoTouch, but not remotely to the same degree), and basically having to learn a whole new platform (which is what you're trying to avoid by getting around Xcode/Objective-C/CocoaTouch, right?).
I also hate JavaScript, so I'm going to be biased against Titanium. But even if that weren't the case - even if I could use a language I do like - the APIs don't tickle my fancy. Or my anything.
Regardless of the dev tools you choose, you will end up having to learn something about CocoaTouch. Whether it's Xcode/Objective-C, MonoTouch, or Titanium, something is going to break or go all wonky on you, and you're eventually going to have to refer to CocoaTouch documentation.
If I were giving a talk on iPhone development (which I have, and which I will be doing again), and if I were to discuss alternatives to Apple's dev tools (which I will), I would still strongly encourage devs to at least work through a few basic iPhone apps using the native tools. It's going to make you a better developer for the platform - period. And you can use this beginning phase to determine if you even want to use anything other than the free Apple-supplied bits. You might not. I've been using MonoTouch because it pleases me - not because it's necessary.
So, to summarize a few basic criteria:
Preference (language/frameworks)
Devices (do you care about non-iPhone platforms or think you might someday?)
Comfort (if you like and know C# MUCH better than Objective-C, there's no reason not to go with MonoTouch)
And don't listen to the naysayers unless they've actually used the tech they're talking about. For example, I've read about Titanium, but I'm not experienced with it - I just know that I don't want anything to do with it on account of my preferences. That doesn't make it "bad" - just something I don't want in my life.
The Objective-C crowd can be impressively zealous. While there are plenty of open-minded devs in it, there are so, so, so many who think Objective-C and Cocoa and blah blah blah are THE last dev tools devkind will ever need.
Ignore them.
If you're worried about support, here's some stuff to consider:
Apple is likely to remain current, as they're the ones making this junk.
MonoTouch is likely to remain current - the Mono peeps have done an amazing job keep up with Microsoft, and I see no reason why they won't do the same with Apple. I'm blown away by what they do. And despite MonoTouch having been released, like, five minutes ago, they already have an update out for iPhone 3.1 stuff. They're serious about this, and I think they're magic. They're the Keebler Elves of the dev world. They sit in their secret layers and crank out stuff everybody (ok - not everybody) likes, but that nobody else would even attempt to do.
Titanium is either going to become an awkward unified API for writing apps for multiple platforms that is entirely its own thing, or it's going to become more and more splintered as the capabilities of different platforms diverge. Yeah, that's a bunch of typical armchair nerdly future-gazing... I should have prefaced this bullet item with "It's my opinion that..." If only there were a way to go back and change it.
Go with what you like. MonoTouch is a "safe" alternative to Apple's stuff. I'm afraid Titanium is going to go down the same old oops-this-super-high-level-platform-abstraction-layer-stuff-doesn't-really-work road that so many other technologies have. But if you're doing something simple, there's no harm in giving it a shot, especially considering that it's free during the beta period.
These are fun and interesting ways you can build iPhone apps. But, for truly rapid native iPhone development, your best bet is the free iPhone SDK and Xcode.
To be honest, the hardest things to learn are the capabilities of the frameworks themselves, NOT the language syntax. But that is an issue you have to tackle either way as these IDEs/Languages still require you to grasp some of the conventions of Cocoa (and Cocoa Touch).
I don't say this as a Cocoa / Objective-C snob, but if you know C (which as a C# dev you do) there really isn't any barrier to entry.
In addition, you will have access to tons of tutorials and sample code that just won't be available for these fledgling translators/IDEs/languages.
Learning another programming language is rarely a bad thing, and as an experienced programmer, your time investment won't be as large as you think.
I've created an open source project http://propertycross.com that helps developers select a cross-platform mobile framework by showing the same application implemented with Sencha, Titanium, Xamarin and more. This project allows you to easily compare a wide range of frameworks in terms of end-user experience, code, IDE, developer experience etc ...
I kinda like the idea of providing means to quickly get a grip on iPhone dev with techno people already know.
I personnaly, as a Java developer, use iSPectrum (http://www.flexycore.com). It also come with an IDE, debugger and stuff, which make it really convenient to develop with because it benefits of all the power of Eclipse Java plugin.
Being based on Java, this also allows to easily reuse already existing code from other java apps, which can be really handy providing that Java is present on almost all platforms (desktop & mobile alike) except iPhone.
Plus it's free for open source projects.
I'd rather consider these kind of solutions, because I don't like the idea of coming back to developing in emacs :) .
I know this is an old topic, but in the interest of staying current, it looks like MonoTouch and other cross-platform frameworks are going to be banned in SDK 4.0. Your only "safe" bet for writing iPhone apps is to use XCode and Objective-C, at least for the time being.
If you're C# programmer why you shouldn't invest some times to learn Objective C. Honestly speaking, it will not take much time from you. But you feels good to work in a new platform with new language. Learning new things all time fascinates me.
There are numerous ways to get on the device. Apple has stated in the SDK license that the only approved way to get on the device is via C, C++, ObjectiveC, and Javascript.
It appears at this point in time that apps built on MonoTouch and Appcelerator Titanium are being accepted into the App Store. Thanks to the license change, there is much fear, uncertainty and doubt on this subject. Apple has scared everyone not doing ObjectiveC.
I would suggest that you do whatever makes the most sense for you as a developer. If you know C# and .NET, you should go with MonoTouch. If you know ObjectiveC or the Mac platform, ObjectiveC is probably the way to go. If you know X and it's on the iPhone, well, X is where I would suggest looking first.