I want to upgrade my iPhone app from iOS3 to iOS4.
Once I upgrade to iOS4, which versions of previous iOS does the app support?
For eg. will it support iOS3, iOS2, etc.
Thanks!
It will depend on what features you implement. If you implement a feature that is specific to iOS 4 (like in-app sms), then that feature will not run on previous versions. In some cases this may cause you app to not function on old versions. Make sure the feature is available at runtime before you try to use it.
In your target's build settings there is 'Base SDK' and 'Deployment Target'. 'Base SDK' is the newest iOS that you want to compile for, while 'Deployment Target' is the oldest iOS that you want your app to function on.
You can set the Deployment Target of your application to the base version of the SDK that you want your app to be compatible with. Once set, your app will be compatible with all versions of the SDK from the deployment target through the current version.
The iOS 4 SDK can build an app that'll run on iOS 3.0—by setting the project's Deployment Target to same—but no earlier. On the other hand, just about nobody is still running 2.x, so that limitation isn't likely to be a problem.
Related
I just uploaded a beta of my app to http://testflightapp.com. I noticed that it is only for iOS 4.3.
How can I support devices from iOS 4.0? Do I have to make the ipa for each framework version?
Any suggestions?
Set the iOS Deployment Target in your build settings to the oldest version you want to support.
Please note that this doesn't automatically make sure that your code actually works on the older API (for example if you use stuff in the frameworks that's only available in the latest version ... )
I have written an app and its base SDK is set to 4.2, and at the moment it is in the app store with a deployment target set to 4.2, I'm sure you'll agree this is a bad idea because I am alienating all potential users who do not have the latest version of iOS installed.
So my question is, when deploying for an older version of iOS, how do I make sure it will run, i.e. how do I check whether I've used any modern API's that are not present in the deployment target iOS version?
The only sure-fire way to make sure your app will run is to test on a device running the older OS version you specify.
Even old versions of the iPhone Simulator (if you can find such) will not do a good job of checking for compatibility.
Most developers who want to support customers on iPhoneOS 3.x have access to an old test device, such as an used iPod Touch (hand-me-down, or purchased on eBay, etc.) running the OS version set in the app's Deployment Target. Otherwise, the developer is just guessing/gambling.
Check the documentation of the libraries or methods you are using. Test on the actually device installed with the version of the OS you wish to support.
Change the Base sdk version to 4.2, target sdk to 3.0 or any.
test the app in simulator as the target as simulator 3.0 r any.
But, when compared to 3.2 , 4.2 version has many new functionalities that do not work on 3.2 version devices.
So take respective steps to do for 3.2 r for 4.2.
The better idea is to find the version of the device , then give the accessibility based on the version.
Thanks,
Bharath
I've downloaded the final version (and never installed any beta versions before) of xcode 3.2.3 with sdk 4, and now I can't seem to find a way to compile my app for a 3.1.3 iOS.
Does anybody know how can I do that ?
As it is, you can't. They probably did this on purpose to discourage new apps compiled for 3.1.3 which foils multitasking.
Instead you can compile for iOS 4 but make your deployment target 3.1.3. This doesn't really require any more real work, as long as you don't use any non-3.1.3 methods/classes etc. and the application can install and run on a 3.1.3 device. You can also then make your application multitasking aware so that it works nicely on a device that does run iOS 4 and is capable of multitasking.
Just a note: the Base SDK may be set at the project level, but you will need to go to the build settings for the target itself to set the deployment target (that setting is not available at the project level).
To expand on Jason Coco's answer:
If you go to the Project Info screen and click Build, you can choose what Base SDK to use (4.0) and then scroll down to iPhone OS Deployment Target version and set it to 3.1.3 or whatever.
However, you also have to go to the Targets section under Groups & Files (red bullseye) select your target and get the Info build page, and set your iPhone OS Deployment Target there too.
Once that's done, you should be able to test it with a device that's still running 3.0 or whatever you selected.
if you want to be compatible with iPhone OS 3.x you still compile for SDK 4.0, but open target settings and choose that application can run on 3.x (iPhone OS Deployment Target). If you did not use any iOS 4.0 specific APIs then your app will run smoothly on 3.x and 4.x, here is a screenshot of setting to change:
Screenshot
After my upgrade to Snow Leopard and Xcode 3.2 (which I really regret a lot!!), Xcode lost all the SDK's. I'm one of those old-fashioned idiots who still want to develop for 2.2.1. But Apple does not offer me an old SDK download.
Now I was clever and made tons of time machine backups. But: What's the preferred way to get iPhone SDK 2.2.1 running with Xcode 3.2? Some guys said that's generally possible. I do hope so because I still don't believe in all those "faked" stats, and besided that, my app doesn't benefit from 3.x additional features so I would not want to constrain my market just for that lazyness.
Any idea?
Regardless of whether or not you're targeting iPhone OS 3.0 or not using any 3.0 specific features, you should always compile your app against the latest SDKs to benefit from bug fixes and performance improvements.
You can compile against the 3.0 SDK and set the iPhone OS Deployment Target to 2.2.1 and still cater for users who are using 2.2.1.
You may find that some methods have been deprecated, but that doesn't stop you from using them until you're ready to move on.
Get the 3.1 final sdk, it has the 2.2.1 sdk in it. On disk its usual location is:
/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS2.2.1.sdk
Also included is 3.0 and 3.1.
XCode 3.2 should have the prior iPhone SDKs available, just make sure you are setting your project's Base SDK setting to "iPhone OS 2.2.1". (Right-click on your top-level project icon in the Groups & Files browser in XCode and choose "Get Info", then go to the Build tab.)
Raffaello and others are correct: you can use the latest SDK and still target (and test on) older SDKs. For example, I'm using iOS4.0 (xcode 3.2.3) and testing on my iPhone 3g running 3.1.3.
To clarify the procedure:
- go to project info > build tab
- set Architectures:Base SDK (most likely) the latest
- set Deployment:iPhone OS Deployment Target to what ever you want (I have the option to go as far back as 2.0).
Hope this helps someone.
Like I said on other threads, the SDK and Deployment Target are different.
You can still use the latest SDK to build for an older OS.
Just go to your Target settings and under the Deployment section set the iPhone OS Deployment Target to whatever you'd like.
Cheers,
Raffaello Colasante
After I downloaded the latest Xcode with the 3.1.2 SDK, I can't build and test for 2.2.1 anymore. I have the 2.2.1 SDK in the proper directory of my Developer folder.
Is there a setting I have to change?
Yes, to choose an older SDK in the Active SDK popup you have to set either the Base SDK or the Deployment Target build setting of your target to a value equal to or less than 2.2.1.
The Base SDK expresses your intention of what API your code is written for.
The Deployment Target expresses your intention of the earliest iPhone OS you want your app to run on.
The Active SDK is your build-time choice of SDK to use, usually Device vs. Simulator. But you will fail if you try to build against an SDK that is older than what your code is written for. If you code is indeed written to compile against older SDKs and/or run on older OS versions, you must express this by setting the appropriate build settings in the Target. Otherwise the Active SDK popup will limit you to what it knows will work with your code.
Where are you trying to select it? As the base SDK?
You should always be linking against the newest SDK version (this is what an Apple engineer told me directly at an iphone dev event) and then set your Deployment Target back as far as you want. You should be able to set you iPhone OS Deployment Target back to the older SDK version.
This is because Xcode uses weak linking so it will leave out things from the newer SDK on older versions, you do need to do some conditional checking for specific API's/functions using things like respondsToSelector if you are using functionality that has changed across versions.