For Android Phones:
IbisPaint X (I use this all the time. It's so easy to use!)
Flipaclip (Although Flipaclip's original purpose is animation, you can use it to draw static pictures too)
Sketchbook (What did you expect?)
Dotpict (A cute 8-bit pixel art app)
For Computers:
Microsoft Paint (Nobody forgets the classic MS Paint!)
Paint 3D (Paint but for 3D art.)
Corel Paint 2021 (A nice app for digital painting indeed!)
Adobe Illustrator 2021 (Another really cool app by Adobe.)
