Aseprite - Aseprite is an art program dedicated to the creation of pixel art.
KiddoPaint - MS Paint in your browser (with emojis 💃😽🎨)
Pixel Art Studio - A purpose-built drawing tool for pixel artists
JS Canvas - Classic MS-Paint redone as a web application
Pixilart - A drawing app for delightfully retro pixel art
JS Paint - JSPaint is a web-based Microsoft Paint remake