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.
Every performance longer than 5 seconds is kept on Metronaut as Temporary Recordings. Temporary recordings are deleted after some time and we keep only the last 20.
If you want to permanently keep a recording press the keep button next to it. Press the Change button to rename its name.
You can also delete recordings by clicking on the bin symbol next to the recording.
You have the ability to delete all recordings by going to Account->Storage in the Metronaut Home.
Note that as of version 2.0 of Metronaut, all recordings are stored locally on your device. They are not saved on our servers, not shared among your devices and are only visible to your device users unless you explicitly share them. This also means that if you delete the App you'll loose all your temporary and permanent recordings on that device.
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. :)