The app, if allowed*, can use the microphone of your device to better detect your sleep phases.
You can manage your sleep recordings too. For this, open the Statistics tab in the lower menu bar. Next to the date, you will see the number of recordings made during the night if there were any. Let's take Friday for example. We see that there are 6 recordings made on Friday. To see advanced information, tap the arrow next to the day.
On the Night Statistics screen you will see the number of recordings and their total duration. In this example, the duration is 2 min 04s. In order to open the edit mode, tap the arrow next to the Sleep recordings tab.
On the Sleep recordings screen you can play the tracks (1). You can also delete a track/delete all tracks or share them one by one by tapping Edit in the upper right corner (2) and choosing the corresponding action.
Hope it helped and if you have more questions, please write us at firstname.lastname@example.org.