Both LG and Samsung provide the ability to take screenshots, draw on them with your stylus or finger and share them. LG’s QuickMemo stands out, because it lets you scribble a note on top of the screen (example: “Buy milk”) and keep them there even as you continue to use your desktop and apps below.
Alternative App: Floating Draw lets you scribble on your screen and either save the results as an image file or leave your drawing as a layer on top of the screen as you continue to use your phone. When running, the free app puts a small pen icon in the lower right corner of your screen. Just tap it, and you’re ready to scribble.