We've updated the firmware to the latest version, so there might be some problems while updating if wrongly operated (see how to update the firmware for iOS). Once it failed, the watch seems to be not working: no matter which button you pressed, there is no LED or vibration; or even the blue LED is flashing, it can't be paired with the phone. Here is what you can do if you are an iOS user.
1. a sufficient battery is necessary.
2. make sure there is no other Bluetooth devices expect for your phone.
3. the app "nevo" is on the latest version.
steps 1: app setting-->forget watch-->app will restart;
steps 2: while reinserting the watch battery CR2025, hold the 1st and 3rd button at the same time. You will see all the white LED flashed once. If so, you are doing it right; if not, please take out the battery and try again;
steps 3: turn on the app, on the first screen "let's get started", long press the screen( the nevo watch image); then click the magnifying glass (the upper right button), a list will pop up with a " NEVO_DFU", press it and it will start updating.
This is for when nevo has failed the updating and was in DFU mode. In this case, you may find nevo in phone BT settings defined as "Nevo_DFU", and not as the normal name, like "Nevo8AA".
If this doesn't help you with your problem, please feel free to contact us by creating a ticket on support.com. Describe your problem more detailedly and a short video would be much appreciated. Thanks.