Post-it Plus is a great iPad app that you can use to digitize your physical sticky notes. The way it works is pretty simple: install the app in your iPad and then use it to snap an image of the physical notes you have. Post-it Plus will then digitize these notes in a format that will allow you to edit, arrange, refine and organize them into different boards.
http://www.educatorstechnology.com/2014/12/a-great-ipad-app-to-turn-physical-notes.html