As you know, how to update the F5/F7 firmware, simply you can go to the HPlus –>Mine –>Firmware version, click it you can update to the latest version. You can download the latest HPlus here. https://www.chinawatchs.com/hplus-f5.html
Actually there is also another way, you can update it manually.
This method also works for NO.1 F7.
First, download the app/firmware here or this one 1.6.3 version. (The firmware is encoded as an application)
There is a new firmware 1.66 version. Here is the latest firmware 1.66.15.
(And this one is the latest NO.1 F7 firmware.)
Second, install and open the app(dfu).
Third, click the select device to pair your watch.
Fourth, find the correct Bluetooth address and connect it. (if your watch is bricked, the device name is started as D_)
Fifth, after connect to watch, click the upload to update the firmware to the watch.
Waiting for the update process to 100%, if firmware updated successfully, the watch will vibrate and a message ‘the firmware uploaded to the device successfully’ will pop up in the app.This version is the latest one, there is a important update in the GPS sports training section.
Just install and find it by yourself, personally I think this update is very useful.