Could you folks try something out in your spare time?

Could you folks try something out in your spare time? I downloaded a few different digital speedometers from the Google Play Store and tried to measure my speed while riding in a car. No luck. I made sure GPS was on (highest accuracy selected with Location Services on), but nothing. I did a Bluetooth Intertnet tethering link to my phone (could open Play Store just fine), but no luck. I toggled things off and on, rebooted, everything I could think of, no luck. Got a consistent speed of zero, even after waiting 3 minutes for GPS to acquire.
This was on a FINOW X5.

Could you download one of these speedometer apps and try and get it to work on any of these round watches? If you do, can you let me know what app, what phone parameters, etc? I’m not using a SIM so I’m relying on tethering. Haven’t tried WiFi hotspot tethering yet, just BT. Thanks in advance for your efforts.

In my case, GPS only works if I have data (from sim or from Wi-Fi, but not by Bluetooth tethering)

Ah, but the question is, with GPS working, will the GPS data transfer over to a speedometer app and give an accurate speed reading on the watch that matches the car speedometer? I’m wondering (1) does it work at all, (2) is the update interval frequent enough for a speedometer app to compute speed, (3) is the GPS data accurate and reliable for the reported speed to remain constant or does it jump all around the place. Hence, the request for others to try it out on a D5/X1, K9/X2, K8/K18/X5, etc. In my mind’s eye I picture folks in the back of an Uber or on a speeding train or metro being able to view accurate speed info on their smartwatches. I’m also thinking, since it’s just GPS and an app making computations on GPS data, the thing should work without any network connection, right? Perhaps even on an airplane?