I have a app with the minimum iOS target iOS7.
I am considering in add some extra features with the apple watch. Theres is any option to maintain the iOS7 as the minimum
You can set your deployment target to iOS7.x and make sure you build against iOS8.2 SDK. You will need to set the frameworks as optional
(weak linking) in your build settings and perform run time checks to ensure you don't attempt anything with them on an iOS7.x device.
Optional frameworks will resolve as nil
in an app where the framework is not linked.