[alatkins]

Just for comparison's sake, Withings Activite watches claim 8 months battery life and have a replaceable (CR2025) battery.

In practice I got ~5 months before I needed a replacement, but that's still pretty decent.

I'd say the comparison is apt given Activites are ostensibly analogue watches with basic activity/sleep trackers built in, with BTLE comms.

[vincentkriek]

The Withings Activite watches sadly have no notification support, so no LED or vibration motor in the watch. That helps wonders for battery life of course.

[alatkins]

Good points, although it does have a vibration motor but only for alarms.