You can find your recordings for a given piece by going on the score of that piece and tapping the recordings button in the top right corner of the score.
We automatically keep 20 recordings, you can decide to save some, send them to yourself or share them with your friends.
You can also delete recordings by clicking on the bin symbol next to the recording.
FYI, you have to allow Metronaut to access your microphone for the App to be able to record your performances. When first using the App, a pop-up will appear asking you permission, then it won't appear again. :)