In recent years, we've seen many companies bring E Ink tablets and monitors with high refresh rates using software tricks. However, there is usually a price to pay: the closer you get to 60 fps, the more ghosting and tearing you see.
Developer Wenting Zhang came up with a DIY project that is ideal for a small E Ink display. He ported an open source Game Boy emulator to the M5Stack M5PaperS3 device with an ESP32-S3 chip and a 4.7-inch E Ink display with a resolution of 960 x 540 pixels. The result is PaperboyS3, a Game Boy emulator that looks very good in the video.
The basic principle is that a full screen refresh on an E Ink display takes a long time, but if you focus only on the individual pixels that change while the rest remains unchanged, much faster operation can be achieved. It also helps that the original Game Boy had only 160 x 144 pixels in grayscale (or rather green). Even when scaled up to double or triple pixel density, the emulator window occupies only part of the M5PaperS3 display, while a static set of controller buttons is located at the bottom.
As Wenting Zhang describes, achieving proper display function when using the CrankBoy emulator was not the only challenge. The M5Stack also lacks a proper speaker and uses only a simple single-tone buzzer. By quickly switching between 4 different audio channels, the buzzer can be made to play chiptune-style music. It doesn't sound exactly like a Game Boy, but it's close enough to make sense.
For those who want to use tactile buttons instead of the touchscreen, there is basic support for Bluetooth controllers. Overall, it's an impressive project with one major drawback: the M5PaperS3 has reached end of life and is no longer available at its original price of $59. It can be found on eBay or from other sellers, but usually sells for more than double the original price.