Xcode 5: about 64-bits architecture and backwards compatibility

Question

I've developed an iOS app whose Deployment Target needs to be 5.0, so the target's Build Settings > Architectures > Architectures value has to be the standard without the 64-bit one (XCode complains about my deployment target if I try to include it).

I've read this post: Xcode 5 and iOS 7: Architecture and Valid architectures dealing with this backwards compatibility, but some things are still not clear for me:

They say in that post that last Xcode update allows to build both 32-bit and 64-bit but only for a deployment target of iOS 5.1.1 and later. I'm targeting iOS 5.0, how should I handle this? Will Apple reject my app if I only submit a 32-bit build and I don`t take advantage of iPhone's 5S 64-bit processor?

And finally they don't explain the difference between Architectures and Valid Architecures values in target's Build Settings, could somebody explain that?

Thanks!

Answer 1

Recommendations

I'm targeting iOS 5.0, how should I handle this?

Based on your requirement it appears the only option is to build the 32 bit app only. This should work on the iPhone 5s in 32 bit mode.

Will Apple reject my app if I only submit a 32-bit build and I don`t take advantage of iPhone's 5S 64-bit processor?

No. It has been publicly stated that 32 bit apps will continue to run on iPhone 5s although there is a known bug where 32bit apps will not support bluetooth operations on a 64 bit device (link). I have submitted a 32 bit app to the store which ran fine on iPhone 5s.

And finally they don't explain the difference between Architectures and Valid Architecures values in target's Build Settings, could somebody explain that?

To read the full explanation see the Xcode Build Settings documentation, but in essence just note the reference to the intersection of the two architecture settings. Actual supported architecture will be the intersection of values (one or the other setting may be empty but not both or no binary will be output).