Have you looked at AutoDirect, Greensheet, or a similar freebie print ad circular lately? You’ll see page after page of classified ads organized in very broad categories, like Trucks, Cars, and Appliances. You practically have to read the whole rag from beginning to end to see if there are any ads that interest you. This should give you a new appreciation for three basic online tools: search, sort, and filter.

We take them for granted in our digital world. But there are some nuances to getting search, sort, and filter right in a mobile application. This chapter explores more than a dozen different approaches.