Build this calendar display using the Adafruit Metro M4 Express Airlift and the Tri-Color ePaper Shield.
A wonderful thing happened when the Metro M4 Express Airlift was released. It opened Arduino sketches to the Internet, freeing them from the confines of their closed environment. It is now officially a "thing" in a world of the Internet of Things (IoT). For this project, the sketch utilizes the built-in Airlift coprocessor board of the Metro M4 Express Airlift to grab the current date and time from Adafruit.io. No Real Time Clock (RTC) is needed here, since Adafruit.io will happily give us the current date and time, and in our local timezone too.
The Adafruit Tri-Color ePaper Shield used with this project is a 2.7" ePaper shield that displays black, white and red pixels. It easily connects to the Metro with no soldering needed since the headers are already assembled on both the Metro and the ePaper shield. The sketch displays the current month using the date and time pulled from Adafruit.io. The ePaper display keeps its display even when power is removed. Once a monthly calendar is displayed, you could unplug it and the display will continue to show the calendar.
Building this project requires no soldering and uses just two parts: the Adafruit Metro M4 Express AirLift Lite and the Adafruit 2.7" Tri-Color eInk / ePaper Shield with SRAM. To make this project portable, you could add a USB battery pack or the Adafruit PowerBoost 500 Shield and a Li-Po battery and insert it between the Metro and the ePaper shield.
If you are interested in ePaper displays for other projects, check out the entire line of Adafruit's ePaper displays.