Sketch Pad Plus is an app with many features, including different colors, by which you can do anything you want in the white space. This app has many advantages like if you need to note something important you can use this app.
Also after playing the game review it in playstore as well as google forms whose link is provided below.
https://docs.google.com/forms/d/e/1FAIpQLSfnXpd0wtgUv9wzRKos4302oQu7LZpKn9crzGxJZnpsZcuNyw/viewform