Location is used only while a trip is running, from Start to Arrived. Your trips, vehicles, places and rates are stored on the phone. They leave it only when you share a PDF, a CSV or a file yourself, or make a backup.
The network carries the map tiles of a trip (OpenStreetMap), and Google's ads, consent form and ad-free purchase. Suggest an improvement sends the message you write, only when you send it. Places are recognized on the phone; your position is never sent.
The full text is the privacy policy.