Follow the usability ABC: Always Be Checking

Test your design, keep it simple and iterate. Keep in mind that mobile is less forgiving than desktop, thus provide fully responsive design which is appropriate to small screens. Applications are used while doing other things, so be sure every process can be saved if an interruption occurs, and completed afterwards. Leave all non-essential information in secondary screens and structure navigation based on usage-driven data and observations. Sort contents based on priority of use, not alphabetical. There are plenty of usability templates and tools online, both free and with subscription fees.