A memo app with a black ink pen and a unique white ink pen
It is like a real one i.e if you want to fix a mistake with a black pen, you need to use a white ink to hide it.
To switch black and white color, tap on the 2nd left icon.
To save, tap on the 2nd right icon and wait for the icon to jump. A thumbnail will appear if the saving is successful. The saved one will be loaded in next launch.
To clear, tap on the last right icon.
Enjoy "Realistic" writing on this app.