This post was previously on the Pathfinder Software site. Pathfinder Software changed its name to Orthogonal in 2016. Read more.

While a mobile app may do a lot of things, it’s essential to design the app so it feels simple to the user at any moment during its use. But how do you generate ideas that will make an app simple?

Try the following approach. List the top ten features you want in your app. These should be the most important things that characterize your app. If you have more than ten that’s OK, but try to come up with at least ten.

Once you have ten (or more) features listed, pick the top three. Now from the top three, pick the top one. Next, set a timer for 15 minutes. Draw some concepts of your app so it only does the top one feature. You may want to use index cards or pre-printed storyboard sheets to capture your ideas. After 15 minutes is up, reset the clock for another 15 minutes and create a new design that contains the top three features.

Obviously, you may do many variations on this exercise. Despite the details, the idea at work here is the same. By introducing constraints (number of features and time), the mind tends to be more focused and often more creative when generating ideas. When one feature is viewed as most important above all others, the design will favor that feature. By trying another feature as the top one, you will likely get different ideas.

Try this exercise on your own or challenge your team to come up with designs. Your time investment will be small but the outcome can be quite effective.