I have a EMF meter app, similar to the teslameter source code given by apple. the app works perfectly on the 3gs reading the numbers fine but on and iphone 4 it does not work at all. Is there some major difference in the compass hardware?
The app is based on the magnetic readings from the compass
No, there isn't any relevant hardware differences.
The iPhone 4 also has a gyroscope, but it shouldn't alter magnetometer data.
Which behavior do you have? Any data at all?
Related
I have been building on top of the iphone augmented reality framework found here
but sadly, on mobiles without gyro (namely the 3GS) it doesn't work (as it states.)
Does anyone know of a fix to make it work with the motion sensors and compass heading instead ? Or would anyone be so bounty-hungry to provide the codes to a such framework ?
I will need a way to either make the vectors work, and if it is not possible, I will need to push through and just use heading only.
CoreMotion do work in devices like 3GS. However, this Framework pARk is for devices with gyroscopes (Runtime Requirements: iPad 2 or iPhone 4 running iOS 5.0 or later)
Gyroscope is a fundamental piece of inertial navigation systems (INS) and thus without it you'll have a severe loss in precision.
Check the paper: "Usability of apple iPhones for inertial navigation systems" for a comparison of the performance of iPhone 3GS and iPhone 4. The author's conclusion is:
However, the tests show that even with the use of filters
it is challenging to build a precise INS using sensors from
common devices because of their inaccuracies and high
error rate. The results show that the iPhone 4 can provide
tolerable results for a short time, but then the deviation
becomes too high because of the error rate. Currently we are
implementing a multi-dimensional Kalman filter to examine
possible enhancements. Furthermore we try to improve the
system by using more sensors from the iPhone 4, e.g. light
sensors and camera.
I believe you should think your app to support only iPhone4 or newer.
Can anyone help me to find some full specifications for the accelerometer of the iPhone 4S?
I tried to search something over or inside apple.com, however, I wasn't successful.
I would like some full specifications regarding the measurements of the accelerometer: measure scale, how often do the readings refresh, mainly everything about it.
The iPhone 4S uses the STMicro STM33DH 3-axis accelerometer and the STIMicro AGDI 3-axis gyroscope. I was unable to find a specifications sheet or product page.
Sources:
http://www.bigigloo.de/wordpress/wp-content/uploads/2011/04/CoreMotion.pdf
http://www.ifixit.com/Teardown/iPhone-4-Teardown/3130/2
The real accelerometer model is LIS331DLH, see this (emphasis mine)
Of the major design wins, Infineon found itself with the transceiver (marked with 'Apple 338S0626') and the X-GOLD 61x (marked '3833') baseband processor. [However], the most notable of parts though was from ST Micro, who provided not only the LIS331DLH 3-axis accelerometer (incorrectly identified as the STM33DH) [along with] the 3-axis digital gyroscope...
The Chipworks webpage also identified it as the LIS331DLH
The specifications for accelerometer are here.
Can you make iphone apps without owning an iPhone? I have a macbook but wondered if maybe there was an emulator you could see your programs on to build your app. All the articles I found were a couple of years old.
Thanks.
You CAN use JUST the emulator to develop apps and for the most part, it works the same as the actual device. Memory and some hardware items behave differently on the device, so it can be be difficult to find bugs before the app gets into the hands of your users, and performance on the device will not be as good as the simulator.
Also, things like the Camera, Location Services, Accelerometer & Gyroscope will not be usable in the simulator.
In theory you can (Xcode comes with a simulator) but in practice I don't think you can. Several things don't work in the simulator or work differently so you won't be able to test if your app works properly.
The practical differences between the simulator and a real device are:
Runs faster than the real device.
Internet access is treated as WiFi. It doesn't emulate 3G.
You can't tilt or control acceleration.
You can touch with one or two (holding alt) fingets, but not more.
It doesn't vibrate.
Some sounds and musics don't run on the simulator.
Accelerators, camera, gyroscope, and GPS return fixed data. Your position reported is always Cupertino, the camera is blank, and the sensors report 0.
It can't be jailbroken.
Keychain doesn't work.
However, that's good enough in 90% cases to develop functional applications.
It is certainly highly recommended so you can actually test on a real device. Apple provides a pretty good simulator for doing the majority of your development on, but things like testing memory usages, performance and making use of features such as a camera, location api, accelerometer, etc, you'll need the device.
Certainly, start developing using only the simulator (if you are not sure you want to do iPhone development), but I would recommend getting a device (iPod Touch is a cheaper alternative) if you decide you want to move forward.
It depends on what you are trying to write. All functions of the device are not available in simulator. For example accelerometer. So if you need that then you can't work without the device. And also the simulator uses Mac environment which is far more powerful, both in terms of processing power and memory. So your app may run well on simulator, but may work poorly and even crash on device. So it's better to have a device for serious development. But obviously you can start learning on simulator.
If you want to write apps that don't suck you will need an iOS device. Period.
Doesn't matter if it's an iphone, ipod touch or ipad.
I never had an iPhone and wrote a dozen apps for it. In fact I still use my old iPod touch 2G for development.
But I wouldn't recommend that particular one for development, because now its end of life and you won't get firmware updates for it.
But last generation is totally fine.
Essentially I'd like to know just how compatible are the iPhone and the iPod Touch. I would like to know if I could buy an iPod Touch (and thus save some cash) and develop iPhone apps on it or if I really should spend the extra money and put up with AT&T and get the iPhone.
What exactly is different between the two devices (other than the missing phone part in the iPod Touch).
Has anyone done this successfully? Or am I crazy for even thinking it?
EDIT
I've corrected the references to iPod Touch in the text so that #person-b won't strangle me..
Also, i would like to make sure that I point out the fact that I really am interesting in the feasibility of developing iPhone apps on an iPod Touch.
As #Chaos noted, the iPhone and iPod touch differ in their hardware features. The iPod touch lacks:
GPS
3G/EDGE cellular connection (that is, it can only connect to WiFi networks)
Compass
Camera
Built-in microphone (the second generation iPod touch supports external microphones; the first generation doesn't)
As for the CPU speeds, Apple doesn't publish any kind of spec for that. However, the iPhone 3GS is definitely faster than the current iPod touch, which is a bit faster than the original iPhone and the iPhone 3G. If your app is CPU-intensive, you should test it on an older iPhone.
Another important difference is the networking capabilities of the different devices. If your app never has to connect to the Internet, then an iPod touch is just fine. However, if you're using the network at all in your app, remember that WiFi connections are nice and stable and fast, but 3G and EDGE connections are slow and crappy and prone to intermittent failure. Your app needs to be able to deal with a crappy Internet connection. You don't actually need an iPhone to test this stuff, though; instead, you can write a script to artificially throttle or interrupt your development machine's network connection. Craig Hockenberry posted a good method for doing this, which you can find reproduced here.
As far as general software development goes, getting an iPod Touch is a fantastic way to get into iPhone app development. I live in Nebraska, where AT&T coverage is spotty at best (my friend's iPhone doesn't get a clear signal in my house). You won't get the bells and whistles of a 3GS, but you'll save on the up-front investment.
I recently purchased a MacBook and a 32GB iPod Touch to do just what you're suggesting - get into iPhone app development on a budget. In the end I plan to pickup several more devices, but just to get started it doesn't make sense to break the bank. I've developed Windows and Linux software but I'm new to Objective-C and the Mac platform in general, so I'm expecting a learning curve. I'd prefer not to be forking over $100 per month to AT&T while I get up to speed.
Here's what I paid for new-in-the-box hardware and software from Apple to get started:
MacBook - $1070
iPod Touch 32GB - $428
iPhone 3.0 OS upgrade - $10.70
All told I've spent $1500 (including tax) to have a viable development platform. According to BillShrink the TCO of a 16GB 3GS with an average usage plan is $2800 (http://www.billshrink.com/blog/iphone-versus-palm-pre-versus-android/). Add in the MacBook and you're up to nearly $4000 in the first two years. I got 2X the capacity for $440...
While I agree that going straight to the iPhone provides the most flexibility, I also think that the iPod Touch is a great introduction to Apple's new software platform. You can save up to $2400 (depending upon how much your current cell plan costs) while getting a feel for the development process.
Update:
One major reason to get the iPhone 3GS is to get OpenGL ES 2.0 support. If you want to do any advanced shader-based rendering, the 3GS is the only iPhone that will work. The 3GS is also nearly twice as fast as the 2G iPod Touch for OpenGL ES 1.1 code. Source: http://toucharcade.com/2009/06/20/iphone-3g-s-vs-ipod-touch-cpu-opengl-es-benchmarks/
No GPS
No 3G Chip
Different CPU Speed (depending on model)
No compass (if we're talking 3GS)
No camera.
Other than that, the apps I'm working on work as well on our graphics guy's iPod Touch as well as on the 3G/3GS
Aside from the other features lacking that other people have listed, the iPod Touch also lacks a built-in microphone, so apps relying on audio input are also a problem.
In general, though, the iPod Touch makes a great testing and development platform for general-purpose apps or games.
I started developing apps for the iPhone on my iPod Touch, here these gadgets are really expensive... and that is a bummer..
The only problem i have encountered while developing was the lack of 3G and the GPS because i wanted to see how my apps will work on 3G compared to WiFi and also i wanted to use the Maps Api but the Touch doesn't have the GPS and i had to find an iPhone to test my app..
If you want to start developing i think the ipod touch is a good starting point also, the 3GS is really expensive(here - Romania - is like 1100 euros - 2 year contracts) and the 3G also(still 600 - euros - 2 year).. so if you only want to play with cocoa and build small apps for free... keep in mind the costs.
The first generation of ipod touch didn't had the volume buttons, the second generation has them..just to confirm
One thing to bear in mind is that the second generation iPod Touch has a more powerful processor than the original and 3G iPhone. If the app you're making is a particularly CPU intense one, you may want to pick up an old iPhone to test against.
There are also a lot of used first generation iPhones out there. You don't need a plan to use them to run apps and get on the Internet via wi-fi. If you really need to test against the older iPhones, you should be able to get one used and not pay AT&T for a subscription.
Yes, this would work fine. They will be more even product lines after apple updates the ipod's to the same internal tech specs as the new iphone. The "iPod Touch" is just like the iphone software wise except for the hardware specific apps.
The iphone has a few more hardware features over the ipod touch like the cellular radios of course, camera, microphone, compass (3gs), and GPS.
So if you are not developing any application that uses any of those device features, the ipod touch should serve you well.
A quote from gizmodo.com
The iPod runs Mac OS X like the iPhone does and we have got unofficial word from inside Apple that it runs exactly the same applications. The exact quote: "they use the same damn binaries".
That quote is from an article that is almost two years old now, and I haven't seen anything to suggest it is incorrect.
So as has been said, as long as you aren't trying to develop hardware specific applications then using the iPod Touch should be fine. Though personally I believe if you intend to develop for a platform you should use that platform. I also understand the iPhone is expensive so I don't blame you for wanting to save some cash. :)
Many people have give pretty good answers. But they have really only pointed out the difference and have not said if you should get an iPod Touch or an iPhone.
GET AN IPHONE
It is simple as that.
It does more than an iPod touch as listed above.
You can use it as a phone and replace your existing phone.
Once your game actually sells you will end up getting an iPhone anyway because you are now making money, you will then need to sell you iPod touch at a loss (you dont really need it).
You will build more than one app in the next year and one of them might rely on the iPhone camera, GPS, or even Video, maybe even compass, you will need an iPhone for all this.
You will now want the internet where ever you are to check you sales stats every day when they come out.
Save you money, buy one device, buy an iPhone and sell your old phone.
The September 2010 iPod Touch has 2 cameras and a microphone. It has the same functionality as the iPhone4 apart from the phone part & doesn't have GPS.
I think it's better to spend money on a iPod Touch 4th gen than on an iPhone 4 (unless you need really accurate GPS coordinates in your app).
Is it possible to simulate movement (ie the accelerometers), microphone and camera in the XCode simulator?
If so, how do you do it?
If not, are there any XCode addins or third party apps that do it? (apart from downloading to an actual iPhone of course).
Thanks in advance!
The easiest way I found to do it is using the Wavefront Accelerometer Data App that can be found in the App Store. All you need to do is add a single file to your application then you can use the accelerometer in your iPhone or iPod touch to send data to your app in the simulator. You'll need a WiFi connection, and a device to use.
You could probably find a solution that runs on the desktop, but you won't be getting accurate real life readings.
I would recommend getting an actual device or your app can behave different than you expect it to. If this is a serious endeavor, you should be able to justify the cost of a device. An iPod Touch is much cheaper but you don't get the phone or camera capability. You can get a headset that has a microphone though.
Those are the limitations, I don't think it wise to develop an app without testing it on a device. I've run into apps that crash all the time and figure it's because they are getting away with stuff in the simulator that you can't do in the memory and cpu constraints of the device.
Microphone works in the simulator. It uses a standard mic input from your mac.
Check this link....
http://media.wiley.com/product_data/excerpt/72/04705009/0470500972-1.pdf
and go to 10 th page..
However, the iPhone Simulator, being a software simulator for the real device, does have its
limitations. Features not available on the iPhone Simulator include:
Obtaining location data — it returns only a fi xed coordinate, such as Latitude 37.3317
North and Longitude 122.0307 West
Making phone calls
Accessing the Accelerometer
Sending and receiving SMS messages
Installing applications from the App Store
Camera
Microphone
Several features of OpenGL ES
In the android simulator the hardware can't be simulated .. but for example for the camera i see an approach to get real information ... Use your webcam .. to do that you can get frames with an app and send this data with a socket to the simulator... maybe it's possible to do that with iPhone simulator.
I see this solution here