Last time we talked about ESP32s starting to become available in the market, and now there is a plethora of boards integrating it, starting from this at about ~7-9€.
It integrates a battery connector with also a charging circuit. Wemos Lolin32
This is another board, with even a small OLED SSD1306. This is very welcome as troubleshooting Bluetooth or WiFi without a screen is cumbersome
For about 13€, this is for the Internet of plants. The PCB can be sticked into the vase of the plant you want to monitor, and trough the GPIO of the esp32 you can start a water pump, or send a reminder to your phone.
It includes a battery charger on the back.
Before deploying, 3D print a case for it, electronics don’t like humidity.
TTgo ESP32 UNO ~8€
The arduino form factor is the rule 34 of microcontroller boards. “If there is a new microcontroller around, there is an Arduino shield compatible board for it, or if there isn’t, it will be made”.
This is not 100% compatible with arduino shields, tough.
It has only one analog pin with max 3.2v input, but digital and power input pins are OK.
Any shield which doesn’t use analog pins and is compatible with 3.3v arduino is fine.