Simply insert SIM in the watch and receiver incoming calls or make calls yourself.
With its bluetooth connectivity option, connect it with a smartphone by bluetooth, so you can also make/answer calls coming on smartphone.
Getiit mate smart watch also has pedometer feature that helps you properly note steps.
Find your phone in if it is in its bluetooth range, either the phone will ring or vibrate.
An additional sports strap is included in the package.
Or on the other hand, find the watch (if present in bluetooth range) by APP in smartphone.