Virtual Virtual Boy (VVB) is an emulator for the Virtual Boy 3D console. You can use it with a pair of cheap Anaglyph 3D glasses or with Google Cardboard to play Virtual Boy games on an Android phone.

Planet Virtual Boy has many free homebrew games available at https://www.virtual-boy.com/homebrew/. The game in the screenshot is Red Square made by Kresna and Nyrator.

Source available online at https://github.com/SupernaviX/vvb

Disclaimer: This application is not affiliated with Nintendo or Virtual Boy in any way.