here is a quite polished english translation for Hey Plus:
firmware1563_ENv6.2.zip
These are instructions to install it:
Instructions on firmware without the need to limit the speed of the Internet.
To execute this instruction, it is necessary that the hey + application suggests updating the bracelet firmware.
1) Open the application hey + -> Settings -> Firmware version
2) Turn off WiFi and mobile Internet
3) Click "Update Now" and get a window with an error and a suggestion to try again. After that, on the phone's disk at
Android / data / com.ryeex.groot / cache / firmware / [bracelet serial number] will create an empty folder with the firmware number
4) Copy the files 0 and 1 of the firmware to the folder that appears from step (3)
5) In the hey + application, select the "Repeat" item.
6) Firmware started, follow the instructions and wait for the end.