Yes, you can conenct 2 mobile phones with Samsung HM1350 bluetooth headset.
No. It does not have HD Voice support.
No. It does not have Active Noise Cancellation.
To connect Samsung HM1350 with your smartphone, please follow the below steps.
01) Make sure that your smartphone's Bluetooth is switched ON.
02) Switch ON your Samsung HM1350
03) Now search for the visible devices on your smartphone
04) select Samsung HM1350
and you're done.