Help boot Samsung S7 device when USB is plugged in

Job ID: 32291892

Budget: $30 – $250 USD

I have to create a system, where only power switch is available. No touch-screen, no button is accessable.

I wanted to use an old Samsung Galaxy S7 edge for the project with the instruction of:
https://forum.xda-developers.com/t/samsung-galaxy-s7-boot-on-charge.3680083/

But at the end I am unable to access the "fastboot" mode.
FastBoot mode worked on another Huawei P10 lite, but there I have no root access.

So I have 2 Mobile devices and none is working to start when power is connected.

If anyone can help, it would be great.
I just have to autorun my app on start, just when device is connected on USB charger, thats the goal.

Regards
Related categories: Mobile App Development Android Android SDK