That little three-lined button is the devil. Whether you call it a side menu, navigation drawer, or a hamburger, hiding your features off-screen behind a nondescript icon in the corner is usually a poor mobile design choice. Interaction theory, A/B tests, and the evolution of some of the top apps in the world all support the same thesis: The hamburger button is bad for engagement, and you should probably replace it with a tab bar or other navigation scheme.