Up to 6 years with once daily updates. For a battery calculator, see Battery Life, Battery Capacity Estimate & Low Battery Flag

See How to change the update rate on the Oyster2, Remora2 and Yabby

Out of Trip - 12 Hour Updates
Then when movement is detected, a fix + upload
When movement ends, Fix + upload

There are no logs/updates during movement by default, it can be enabled.  

In urban environments, within 30m accuracy is typical. 

YES! The Yabby Wi-Fi does not connect to Wi-Fi networks to send data. It simply detects what networks are nearby, and then we can determine the device's position by sending this information to Google's Geolocation service. It doesn't need to connect to the network to see it is nearby - and we still need a SIM card! For more details on how the location is obtained, see WiFi Geolocation on DM Devices

The device will fall back to the cell tower location. It will report the cell tower it is checking into to the server - which allows us to get a fix with accuracy of around 1km. This should be a rare event - but is still useful