How to connect T900 Ultra Smart Watch with Phone/ ZTFit App

T900 Ultra
CPU: YC1133
Dimension: 49*10*10.7mm
Shell: Titanium alloy case
Strap: Standard silicone strap, suitable for 44/45/49mm strap
Charger: wireless magnetic charging
Screen: 2.09 inch HD LCD screen, 425*518 resolution
Support: Android 5.0+, IOS8.0+
Battery: Lithium-ion polymer battery, 230mAh
Bluetooth: Dual Bluetooth
Support: Heart rate, breathing training, blood oxygen, different sports modes, Ai voice assistant, pedometer, sedentary reminder, sleep monitor, BT music, dialer, alarm clock, calculator, stopwatch...
T900 Ultra 2
Battery Capacity: 360mmAh
Screen Display: 2.19 Inch IPS Color Display
Screen Brightness: 80%
Heart Rate Monitoring: Support
Blood Oxygen Monitoring: Support
Build-in Game: Support
Body Material: Aluminum Alloy+IML Injection Molding Process