Ending a ride is only possible at a parking spot. The parking spots are shown as markers on the map. The app will use your phone's GPS to confirm if your location corresponds with the parking spot location.
If your location is confirmed, the main button changes to 'Lock & End Ride'. Tap the button to start the locking process.
When locking is completed, the ride is ended. A receipt screen shows the details of the ride you just ended.
In most cases, a bike can be returned to any parking spot on the map. In some cases, the bike should be returned to the parking spot where you picked up the bike. In that case you will be warned before starting the ride, and all other parking spots on the are disabled.