Does Speedometer work on Apple CarPlay?

Yes. Speedometer is a native CarPlay app, which means it runs on your car's built-in screen alongside Apple Maps, Music, and your other CarPlay apps. When you connect your iPhone to CarPlay, you'll see Speedometer's icon on the CarPlay home screen — tap it to view your real-time GPS speed, current trip stats, and route on the dashboard. The iPhone display can show something different (or stay locked) while CarPlay handles the in-car view.