Modern mobile device screen sizes vary significantly, from watches to phones to tablets. Android in particular has supported varying screen sizes since 2009, and is currently being installed on large format touch displays over eight feet diagonally. These extreme variations present significant challenges to app developers who desire to support all devices within a single application. Squid is a handwriting, note-taking application with well over two million installations and a 4.2+ star rating in Google Play. Although originally designed for tablets, we have adapted Squid to run effectively on phones and more recently large format displays. In this paper we report on UI/UX challenges that we faced and decisions made to overcome them.