My newest purchase is the so called Sonoff mini, a very small device that can build in a wall mounting box. The excisting sonoff software had to be adapted because this thing has no possibilities to connect a sensor and one can't see the leds on the board. Moreover this thing is equipped with an ESP8285.

The promising "diy mode" realy sucks. I had to connect the device and a laptop through an accespoint (mobile hotspot) that i had set on my smartphone. I could'nt use my normal windows 10 pc to establish the connection. This only worked on a laptop. Anyway, after some hours i saw the device in my diy tools app. Next i spent a half day to find out that it is impossible to flash software on it over the air. Nobody knows why. So i soldered 4 wires on the very tiny solder pads on the board and flashed them at the old way. This worked fine within 15 minutes!.