Paper by WeTransfer - A collection of creative prompts
Imoji - Turn selfies or any photo into stickers you can text
Milanote - Milanote is a note taking app for creative work.
ScribbleBoard - iOS8 Keyboard for hand drawing your messages
Astropad - Astropad is a free form drawing tool designed from the ground up to take advantages of the features offered by an iPad.
DrawType - The Drawing Keyboard