After switching to Xcode 7, app size grew from 9 MB to 60 MB, is there a fix?

Question

I\'ve been going backwards in Git history to find the cause of a humongous file size change, but the only real reason I can find is the switch from Xcode 6 to Xcode 7 GM.

Answer 1

Most likely caused by BitCode, I have seen the same growth however once deployed from the App Store the app size hasn't actually grown.

You can disable BitCode in your app and the other targets as well and you should see a shrinkage.

Answer 2

It is expected that the size of the swift dylibs, and your own code, will be significantly larger in the .xcarchive, and when you export for store distribution, due to the inclusion of bitcode. This additional size will not be reflected in what actually gets delivered to your users, so it should not be a problem. When you submit your app to the store, the store will process it to strip out the bitcode, and that processed version of the IPA is what your users will download.

If you do any type of export from your archive except a store export (e.g. save for ad-hoc deployment), we will locally strip out the bitcode (and even recompile your binaries from bitcode first, if you leave that option checked in the export workflow, to recreate what will happen on the store), so you can see how big your app will actually be. TestFlight will also strip bitcode for you and show you your true app size.

You should also be aware that your app's size can also be reduced via app thinning, which you can read about at https://developer.apple.com/library/ios/documentation/IDEs/Conceptual/AppDistributionGuide/Introduction/Introduction.html. You will likely want to perform an ad-hoc export to see the size of each thinned variant of your app anyway.

Answer 3

Embedded Bitcode is the reason.

Assuming you don't want to disable ENABLE_BITCODE, you can strip the debug symbols.

See http://oguzbastemur.blogspot.com/2015/09/xcode-7-and-increaded-binary-size.html as stripping debug symbols away before embedding bitcode is one of the options you can do.

Answer 4

We also had this problem with Swift 1.2. See How to prevent SwiftSupport libraries to be included twice for my original question about this same issue.

I am pretty sure this is a toolchain issue.

Answer 5

I've been testing a lot of settings and combinations and it seems the file size of bundles created by Xcode 7 vary a lot depending on both the device and the version of iOS. Also, the TestFlight builds are now huge compared to before, but the good news is that once on the App Store there hasn't been a huge increase (although I am seeing about 1–2 MB added to the bundle size compared to before).

Here's a few samples to show variance between TestFlight, App Store and devices:

TestFlight, iPhone 5s on iOS 9.1
35.6 MB

TestFlight, iPhone 6 on iOS 8.4.1
70.1 MB

App Store
11.8 MB

The App Store size was identical on all devices I tested. I haven't tested it on iPhone 6 Plus though, it's very possible that the bundle size would be larger since it uses @3x assets.