I like this app because of the nice graphical effects. However, I'm having a hard time using it. I'm using the iOS version. I put the settings on 1080p and 60fps because I'm using it for YouTube content creation. The app crashes very often, either during startup, or right when I'm about to end a screen recording. About half the time, instead of giving me the option to save to camera roll when I tap on the screen when the song is done, it just crashes instead.
Another issue is that the first notes of the imported MIDI files do not show up on the piano roll. The audio plays, but the notes themselves do not show up. I have worked around this by leaving an empty measure before the songs start when I export the MIDI files from my notation software.
I am also having issues with the video renderings themselves. Often, the beginning of the video gets cut off and the video abruptly starts in the middle of the piece. Sometimes, the video looks fine on my camera roll and Google Drive, but then when I download it to my computer, the video file gets corrupted and starts playing in the middle of the song and the audio is completely out of sync. I don't even know how this is possible, since MP4 files aren't supposed to edit themselves just be being downloaded.
I can't wait for the Windows version to come out.