Very frustrating app

Unfortunately this would be a excellent app, where it not for the fact that it doesnt respond well to the pinch command - when you first load a picture you can resize them without too much difficulty, then suddenly the pictures dont respond to your touch and pinch imputs - your fingers slide across the screen without response.
since I bought the app specifically to resize pictures for ios7, the fact that I am finding it hard to do so is quite frustrating.

John Aquilecchia about Wallax - Wallpaper Editor, v1.0.1