A:Answer No.
The phone or PC is used to set an alarm, but the band will vibrate at the set time without the phone or PC being on.
Turning the sleep mode on and off is done by rapid tapping on the Flex. The PC or phone can be off while sleep is being tracked. Even if the sleep mode is not turned on, the Flex still tracks sleep. When the phone or PC is turned on one can entered a time of going to bed and of getting up; once the Internet connection is made, the information is synced.