I am a little curious what happens in the following situation. You have an existing app on the iTunes store (with customers) that uses iOS4, you then release an update to the app that uses a newer iOS.
folks that have upgraded to the "newer iOS" will get the update.
What will happen to those that have not updated, will they still be able to use their old iOS4 version?
Your "deployment target" is what matters. Setting the deployment target allows your app to set it's minimum required OS version. Many developers like to set that as far back as possible, unless your app depends on a features only available in a new iOS version.
Lets say you have an app compiled with the iOS 4 SDK and set 3.0 as the deployment target.
Users with iOS 3 or iOS 4 (and iOS 5) can download your app and use it.
Now you release an update compiled with the iOS 5 SDK and set 4.0 as your deployment target.
Users with iOS 4 or iOS 5 can download or upgrade your app and use it.
Users with iOS 3 that have purchased your app already cannot upgrade, but they can continue to use their existing installed version.
Users with iOS 3 that have not purchased your app yet will now have no way to do so.
Apple will only keep exactly one version of your app on the app store.
Unless they download the newer version, they will of course still be able to use the old one. It's possible however that they download the update unintentionally via iTunes on the desktop. The App Store on the device itself would check if the device's OS version is compatible with the app being downloaded, but iTunes does not, so it would replace the old version in the iTunes library, leading to the app being removed from the device when the user syncs it (because the downloaded version cannot be installed).
So, for existing apps, you should keep your deployment target as low as possible and decide at runtime which additional features of a new OS version you can use. This way, you can keep compatibility with older OS versions, but still provide additional features to those who have upgraded.
Usually (although not always), new OSes are the same as the previous ones but with new features. Older versions of apps often work with the latest OS but don't take advantage of the new features. The only problem users usually have is crash problems but it all depends on which APIs you use in your app.
Additionally, updates are never 'forced' upon a user - they are always optional. When it is a case that the app only works on a version of iOS which is higher than what the user has, then the update will not be offered to the user at all. They will still be able to use the older version that they have installed on their device. Apps have no expiry date.
If you want to retain compatibility for as many iOS versions as possible, you can set your iOS deployment target to the minimum OS you want your app to be compatible on. The SDK version number should not matter, but to support the latest iOS features, you would need the latest iOS SDK.
You will still have to check your APIs compatibility with the version you are targeting as a minimum OS. Look here and search for "API Diffs". Each document lists changes to the API for that iOS version. This will lists new and removed APIs as of that version. For example, UIPrintPaper, which is listed in the iOS 4.1 to 4.2 API diffs document, is a new API to iOS 4.2. So, when running on iOS 4.1 or earlier, the app will crash when calling that API. Using #if __IPHONE_OS_VERSION_MAX_ALLOWED <= __IPHONE_4_1 around your UIPrintPaper snipper will fix that problem.
Related
I currently have an app in the app store that works for iPhone users running iOS version 3.0 or newer. My next version of the app is going to use ARC, so it will only work for users running iOS version 4.0 or newer.
According to this answer, the users will be able to download the newer version, but it just won't run when they try to run it.
Is there any way to prevent users who can't run the app from even downloading it from the AppStore?
I haven't tested this recently, but in February 2011, and iOS 4.x, I had users who couldn't download my app as there device wasn't running the required version of iOS.
They received a nice explanation message on their device, courtesy of the App Store app, when trying to download the app directly to their device.
I'd be very surprised if this wasn't still the case.
So, set the deployment target in your target build settings, and let the App Store / iTunes take care of who can install it.
That was for new installs, and it be different for updates (rather than new installs) but again I'd be surprised if this wasn't handled by Apple for the sake of a better user experience.
UPDATE
I dug out my old iPhone 3 which reached the end of the road at 4.2.1 and resynced it with iTunes - the latest apps that require 4.3 etc are ignored, and are not overwritten with incompatible versions, as I would expect.
I also tried to update my own app (I'm a developer), requiring 4.3 and above, from the store via the device itself, and got a polite pop-up alert saying the app requires iOS 4.3 and above, again just as I'd expect.
The app was previously compatible with < 4.3, and somewhere along the line I bumped up the minimum iOS version requirement, so it is definitely possible.
So, you should just set your updated app's 'deployment target' version appropriately, and it will only be updated on compatible devices.
No. A new higher minimum Deployment target will prevent a user from installing an app on a device with a lower OS version, but will not prevent them from downloading the app using iTunes on their Mac or PC, even though they can't install the update once downloaded.
Hi I am new to the iPhone App development. Currently I released a small application to App store having deployment version 4.3. But some users are not able to download and install the app due to version compatibility. I searched on internet but I didn't get much solution. Now what version should I set while deployment so that every user can use the application?
You should set your minimum deployment version according to API methods you use in your app, i.e. if you use methods from iOS 5 SDK and don't make your app backwards compatible (with support for older versions of iOS), you should set min deployment version to iOS 5. How would you care about users who don't have newer iOS installed is another question.
Deployment target is the minimum version of iOS that is going to be supported by the application. It means iTunes store will allow the users downloading this application having same or higher iOS version on their devices.
To achieve it developer should take care while using the APIs. The API version should not be higher than deployment target iOS version. If you need to use higher API, you should use
[UIDevice currentDevice].systemVersion to check the target device version.
You should set the Deployment target to that of the lowest OS device upon which you have actually tested that version of your app. Many developers keep or borrow an old non-upgraded iOS device just for that purpose. Otherwise your customers become your alpha testers.
go for 3.0 if your code supports that,
maybe that code changes are needed.
I have an application that I would ideally like to run on all iOS versions, however I think Apple accepts apps only from a version and above (3.0 I think, but not sure). So my question would be, what's the minimum iOS target version you can send in review (and get accepted). If anyone with greater iOS publishing experience would answer my question it would be great and maybe point out some places where I can read about it.
Many thanks!
Sometime last year, an Apple DTS employee posted (and later clarified) on the iOS Developer Forums that the App store would no longer be accepting apps with a Deployment Target lower than 3.0. That might indicate that a lower Deployment Target has or will become grounds for an app to be rejected.
I would never set the Deployment Target lower than that of the lowest OS version among the devices I plan to use to test the app before submitting it to the App Store.
Also, the installed based of devices which haven't been upgraded to 3.0 or above might be too microscopic to be worth a developer's time or effort (unless you happen to still have and use one for some reason).
ADDED in 2013: App store submission now requires that the app support the 4" display, which requires iOS 6.0 or later, which allows a minimum deployment target no lower than iOS 4.3
To back up what hotpaw2 indicated, this is from the News and Announcements for iOS Developers on June 29, 2010:
Make sure that your applications are
compatible with iOS 4. All new
applications and updates to existing
applications must be built with iPhone
SDK 4. In addition, the App Store will
no longer support applications that
target iOS 2.x.
ok... strangely Im having a hard time verifying this... but it's my belief that you must build your app with the latest base SDK (4.0), but you can target an IOS version all the way back to 2.0. Ill continue to try to verify that.
You can only build your apps with the SDKs you have installed.
Since XCode will nuke your old SDKs whenever you upgrade (unless you install XCode elsewhere), it is assumed that you will always be building using the latest stable SDK version. This is in contrast to, say, Android, which will always retain SDKs whenever you upgrade.
Your deployment target can go back as far as you want, right back to 2.0 - but you may find it difficult to actually test it on that platform! Most people would just target 3.x upwards, which gives you as close to 100% coverage as makes no difference.
Let's say we have an application with a deployment target set to 3.0 and we want to raise the deployment target to 3.2. Normally, the App Store won't let the App be installed on devices with an IOS version less then this, but what about devices which already had the App installed prior to the update? Will they see the update but won't be able to install, will they just not see the update or, heavens forbid, will be able to install and the app just won't start?
I searched everywhere for this, but I can't find anything about raising the minimum OS version for an app update.
Thanks!
From my experience those updates just won't show up as available.
When I upgraded OS on my device from 3.1 to 4.1 about 10 available updates appeared immediately in App store app - so that should be the actual behavior.
In addition to only showing supported updates, the store now offers the "last compatible version". This lets people download an app even if their device doesn't support the most recent version. Unfortunately this means that some people could still download an older version with bugs you have already fixed. There may be a way to disable this, but none of my app updates have introduced new requirements, so I can not test.
It's nearly a safe bet that they won't be allowed to install it. A similar situation is iPad apps or Mac apps which won't display in the App Store on iPhones and iPods.
I say nearly because the updates should not appear to older users on their iOS devices. The risk, however, is when users sync with iTunes, or if they update with another device. The new version of the app is now associated with their account, and will ruin the install on the older device if they try to sync it with iTunes.
I am getting a fat binary when I go to upload, and I want to make sure that my application can run across 3.0, well even 2.0. Is there a specific way to make sure that this will show when I go to upload. I am not using any specific iOS 4 features, and I only have iOS 4 in my xCode. How can I test different iOS version?
The only way as I could think of is test your app on real old OS version devices. Since Apple prefers its users to upgrade to new OS version as soon as possible, they don't actually provide an official way for developers to test such backward compatibility.
Another relevant questions would be, "can I downgrade my device OS version to an old one, so that I can test my app on them?" I once did a research on SO and other Apple forums, and the result I got was NO, we developers don't have a way to "officially" downgrade our device OS version. Yes there are exceptions, you can try jail-breaking and then downgrading.
For jail-breaking / downgrading your OS version, check this post, A TimeMachine taking my iDevice back to 3.1.2? .
Edited: It's actually pretty easy to make sure that users with old OS versions can downloaded and install your app. All you need to do is set the Deployment Target in Xcode to the lowest OS version you want (iOS 3.0 would be the lowest in Xcode 3.2.5).
However, you need to bear in mind that such Deployment Target only ensures that your app can be downloaded and installed on such old version OS devices. They don't ensure compatibility during runtime. You still need to test your app on real old OS devices to ensure compatibility.
I dont think u need to worry about app version 3.0 below because it is not supported anymore. but how to test on different version, make sure change the iOS deployment target as Thomas refered.
There is no currently supported way to do this.
No current Simulator or Xcode tool will ensure that an app is completely compatible with an OS version older than the SDK used. The 2.0 SDK is not compatible with the current development tools. There is no officially supported way to downgrade a device.
Furthermore, Apple no longer even accepts app submissions that have a deployment target lower than 3.0.
Even most old 1st gen devices, if you can find one on eBay, have been upgraded to iOS 3.1.3. But if you have access to an old device running iOS 3.1.3, you can use that for testing. Many developers keep an old used iPod Touch around for just his purpose.
People with devices running something older than 3.1.3 are not only a really tiny percentage of the installed base, but are very unlikely to be still buying apps for that device. Even large developers with staff and legacy hardware available for this testing rarely waste the time on this market.
Look into Project -> Edit Project Settings -> iOS Deployment Target: 3.13. And then build?
Edit according to comment: You still need to ENSURE your code is within the runtime scope, i.e. do checks like 'respondstoselector' before calling methods in question.