How to know which architectures are included in an iOS binary framework

Use the the lipo command with the -info or -i option (example using StuffManager.framework):

lipo -info StuffManager.framework/StuffManager

The output will be something like this:

Non-fat file: StuffManager.framework/StuffManager is architecture: arm64

or

Architectures in the fat file: StuffManager.framework/StuffManager are: x86_64 arm64