The real problem with Vivaz is its design. The battery in my one week old Vivaz lasts 36 hours with 20 minute usage. No apps are running and GPS, Wi-Fi, and Bluetooth are disabled.430-440 hours of standby is advertised.Fido tech support was not helpf...
I would be careful buying a battery from eBay or similar places. There is a good chance getting a fake one.From my experience with aftermarket batteries they may not have the advertised capacity and die quickly. One of the cheap places to buy a knock...