Xcode - Delete application before running on device

The only way is to delete it manually. There's no way to have xcode delete the app from a device before running each time if that's what you were asking. Sorry, it would be a great feature, but for now, there's no way to do that. Not even on the simulator.

I think you should file a bug/feature request with apple though! That functionality would come in handy for me!

Yes you can.

Get https://github.com/libimobiledevice/ideviceinstaller

Which brings you the ability to use ideviceinstaller --uninstall <app-id> in the bash environment.

Then do a script in your build configuration in xcode, such as: http://www.runscriptbuildphase.com/