The board is 25mm x 59mm, which means it can fit into the standard breadboard nicely, and each pin will be accessible.
The board can be powered by 3.7V li-po battery.
In deep sleep mode, the board consumes only about 13µA. This is a pretty good result and will let the device work for a long period of time on a battery.
You may power the device from battery as well as from the USB at the same time - useful feature if you're making some quick fixes to the "already deployed" device.
The IO35 pin of the ESP32 is connected to the (switchable via IO32), to avoid excessive current draw input voltage divider, and can be used to determine the battery level of the battery.
Many ESP32 boards don't do it, which is a problem, because not all revisions of CP2102N enter suspend state correctly, which means they draw current (a few milliamps) when they are not supposed to (e.g. when powered on from the battery). This issue is fixed in our board.
ESP32 has a bug that makes automatic reset during flashing with tools such as esptool.py not happening, and thus requires manual user intervention.
Our board also incorporates the fix for this problem.
Me and dextero. The board is an absolute overkill, built to monitor soil moisture and eventually to help reminiding about watering plants more often ;-).