Overview
- Section 23 of the road traffic regulations prohibits operating or carrying ready‑for‑use devices that indicate or interfere with speed enforcement while a vehicle is in motion.
- A ruling by the Higher Regional Court of Karlsruhe establishes that passenger‑operated warning apps can still make the driver liable.
- Police may check device settings during traffic stops and can confiscate or even destroy radar detectors and active app setups found in use.
- Permitted options include checking routes with such apps before departure, relying on radio warnings during trips, and using multi‑function devices only with the camera‑alert feature disabled.
- Rules vary across Europe, with strict bans and heavier penalties in countries like France and Switzerland, some allowances for GPS‑based alerts elsewhere, and TomTom removing its Android overlay warning option while warning users about legal limits.