I purchased the ESP-01M module for my Mini Blimp project. I thought it was smaller (it is) and lighter (it is), and I liked that the way it mounts is such that the antenna is not on the PCB itself.
I also liked that it doesn't take up much real estate- the blimp project requires as little PCB material as I can get away with. I figured that the ESP-01M module that is oriented perpendicularly to the board would help.
A connector for this board doesn't seem to be available, so I decided to make a breakout just for the card edge module. I'm also testing:
- Tag Connect pinout and programming
- Eliminating the switches needed to program the ESP on reset/ GPIO2