Our iOS apps use the standard App Store EULA provided by Apple: http://www.apple.com/legal/itunes/appstore/dev/stdeula
This permits developers to collect anonymous usage information (see section b).
Our apps collect anonymous data so that we can track usage. However we do not track any personal information or any data related to your personal use of the app (for example file names etc).
This is the data we collect:
Device version; iOS version; App version; Current language.
This information helps us determine things like when the is time right to drop older iOS versions and devices; how many active users we have; how widely used translations are etc.
The only data iOS developers receive from Apple are sales numbers, so additional, anonymous, data from active users is very useful and helps us improve our products.