Hi!

What Fitness tracker work with the GYM app?
I have got this one:
https://www.amazon.de/HETP-Blutdruckmesser-Schrittz%C3%A4hler-Aktivit%C3%A4tstracker-Schlaf%C3%BCberwachung-Schwarz/dp/B07C2XLJ9X/ref=sr_1_1_sspa?ie=UTF8&qid=1551095201&sr=8-1-spons&keywords=heft+fitness+armband&psc=1

But it's not connecting to the GYM app and the phone. The fitness tracker rejects the connection. It (only) works with the H Band 2.0 app.
The GYM app finds the Bluetooth device called "W8" but it's not working.

Can someone help me out please?