Good but unstable

I definitely like what these guys have done with the app! It now supports iPads and can record video alongside the audio. Its loads of fun to use and, because of the "bare-bones" style of the recording process, it is left entirely to the singer to make the song their own, voice-breaks and all.
However, my iPad mini (1st gen, currently running iOS 9.1) crashes quite frequently. Id like to see that fixed. Also, the button to sing the song that you are hearing doesnt work for me.

Stat. Stud. about Wurrly: The Ultimate Singing App, v2.2