import kivy
kivy.require('1.8.1')

from kivy.app import App
from kivy.lang import Builder

root = Builder.load_string('''
#:import stopTouchApp kivy.base.stopTouchApp
Button:
    text: 'Exit'
    on_release: stopTouchApp()
    #on_release: app.stop()
''')

class TestApp(App):
    def build(self):
        return root

    def on_stop(self):
        print 'stopping'

if __name__ == '__main__':
    TestApp().run()