In many regards, mobile is no longer just the future, it is critical to the present as well. Mobile internet usage now makes up a majority of worldwide internet usage. Applications that do not feature mobile usability are quickly becoming a hassle for users, and ultimately obsolete.
Unfortunately, developing for mobile is not as simple as taking desktop development practices and squishing them to fit on a smaller screen size. When considering the development of a mobile application, whether a brand new app or a modernization of a legacy app, there are a number of factors to take into account, from differing operating systems to varying display resolution and densities. Here are some things to think about:
1) Think About Navigation
Touch screens are the norm in mobile. Fingers are bigger than cursors, so any interaction points should be at least 44 px in size and be separated by whitespace. Rely on gestures when possible.
2) Retool Your Content
The smaller display space necessitates prioritization of content. You cannot simply take your existing single page app or website and try to replicate everything – take the most important content and put it at the top. Use search to help users find secondary information quickly without unnecessary scrolling.
3) Optimize Load Time
74% of users expect web sites to load within 5 seconds. This is even more difficult given mobile bandwidth constraints. Avoid hefty image files and complicated style sheets. Optimize the loading of data. Use browser developer tools to monitor page weight and set a performance budget (ex. no more than 700 kb) for your whole site.
4) Test Your App In the Field
For mobile, remote testing is often more effective than on-site testing, since it can be done in an environment more like its final use case. Mobile testing needs to be moved out of the lab and into the wild.
Although creating usability in a mobile application requires learning a different set of standards than traditional desktop development, the rewards are well worth it. A well thought out, easy to use mobile application will pay dividends in user adoption and satisfaction.