App not working on iPhone 3gs

Question

So, I delivered a app that I made in xcode 4.0.1 ... and then i had to make it work properly on iOS 5 also (there were some things not shown properly). Anyway, my client mailed me that the app doesn't work on his iPhone 3GS. What should I look for ?

EDIT: It actually crashes only when opening a webview that streams a youtube video.

Answer 1

Thinks you should check:

• what deployment target is selected -> at least should match your clients iOS Version
• what build architectures are selected in the build settings? Is it only ARM 7 (i am not shure if 3GS already supports ARM7 so you can change it to ARM6+ARM7.
• since i understand from your question that you deploy adhoc there is maybe the possibility of a new/changed device and the UDID does not match any more

Answer 2

To find out the reason of "not work", You should read the crash log. There are a lot of possibilities, for example, 3GS has less memory, which can cause system kill you app more frequently.

If the app had been distribute on the appstore, you can get crash log from the iTunes Connect. In the iTunes Connect, select "Manage Your Applications", Select your app, and the "View details", then you can find the "Crash Reports" link.