This is a simple remote for controlling ESP8266 and ESP32 based robots/vehicles. It is built around the Adafruit QT PY ESP32-S2 (uFL) and the Adafruit Mini I2C Gamepad. It fits a 1000mAH LiPo battery, a 13x6x6mm switch (sorry, I don't have a link to this one), and a uFL to RP-SMA cable for an external antenna.

The circuit boards and switch press fit right in and, because I wanted to keep it as compact as possible, they need to be glued in place. The battery is held to the back of the Gamepad by a piece of double sided foam tape. Instead of using the QWIIC/STEMMA QT connector on the Gamepad, I cut a QWIIC cable and soldered it to the back of the Gamepad. There's just enough room at the rear of the ESP32 board for the QWIIC cable to plug in. The negative of the battery is soldered to the GND pad on the back of the ESP32 board and the positive lead goes through the switch to the Vbat pad. I wish I had picture of the inside, but I didn't think to take any before I glued the cap on. You don't have to glue the cap on, it's a decently tight press fit, but I glued mine because I'm planning to throw this in my backpack where it'll see some abuse. 

The remote code I'm using and a simple receiver example is on my github here: https://github.com/Darkextratoasty/Mini-Remote-ESPNOW I use the ESP_NOW protocol instead of WiFi or Bluetooth because it's much simpler and has better range.