Cant calibrate on iPhone 6

Impossible to get the iPhone 6 to stay at a 90° angle because of the curved edges. Cant calibrate keyboard, cant even get started with this app. Also disappointed that you need to buy full version to unlock basic typing. Only games with free version, making app a novelty even if it did work with iPhone 6.

Rlouisd about Paper Keyboard - Fast typing and playing with an alternative printed projector keypad