The size of the board is the standard size business card 8.9 x 5.1 cm. On it there is 2.7" GDEW027W3 e-paper display from Good Display (2 or 3 colors both work just fine). One thing that is very important to me is that the device is very slim. This is why I chose LP103053 90mAh battery. It does not have a lot of capacity, but in regular user it should be quite enough for a month or two. The BMS consist of protection, charger and a fuel gauge. Continuing with the slim theme, the USB port and the flat flex connector are chosen, so they have the flattest profile possible. To be able to store images and files we have W25Q64J flash. It is very popular and there is a lot of code for it. On the "entertainment" side we have a RTC and an environment sensor BME680. Everything is tied to a nRF52820 Bluetooth 5.3 SoC.