The app will be running in the background all the time, but it only wakes up when your start moving.
You do not have to tell the app when you are riding - it does this automatically.
The app is designed to passively run in the background, only ‘waking up’ when your phone detects you are moving locations.
When the app ‘wakes up,’ it uses various pieces of data to determine if you are in a car or riding a motorcycle.