xcode - IOS architectures and framework creations -

xcode - IOS architectures and framework creations -

what should architectures framework/library building ios devices? i386 relevant architecture ios framework? a framework consist of headers files , archive file. how can create archive file? now when build library project creates .a file. difference between archive file , .a file?

update

i using below command creating framework

xcodebuild -scheme myframework -sdk iphonesimulator -arch="armv7s" -configuration -release targeted_device_family="1, 2" valid_archs="amrv7 arm64 armv7s"

but getting failed next message:

no architectures compile (archs=i386, valid_archs=amrv7 arm64 armv7s).

why ios framework need "i386" architecture?

yes, can create own framework, check out on github https://github.com/wshcdr/ios-universal-framework

ios xcode xcodebuild