Valid architectures of iOS devices?

iOS Devices are powered by the processors based on ARM architecture, comes in different in versions developed overtime, each one added with some improvements.

iOS developers should ensure to include the valid architectures in project build settings before building the application just to make sure that application runs on all targeted devices.

Apple dropping support for old architectures over the time, the Xcode versions which supports armv7 and armv7s no longer supports armv6. There are some others ways to support all architectures though.