+1: a design lesson
+1 can be compared to Mr Mood: it is an app designed and developed quickly. Even though these two apps can prove themselves to be useful, they are mostly experiments: they show our "vision".
Counting things is an easy task. However, the existing iOS apps dedicated to this particular task are often overdesigned. They are maybe beautiful but the primary goal — counting things — has been lost along the way. They are not focused. They are not well designed.

The purpose of a counting app is to view and manipulate a counter. The app is therefore split in two parts: a part to display the counter value and the other one to control it.

Incrementing the counter is the main task so it must be easy to do. Also it should be easy to use the app with one hand. So we chose to display the "+" button right above the counter in order to make it easily reachable with the thumb.

Of course, decrementing the counter is also important but, in our opinion, slightly less than incrementing it: the right place to display the "-" button is at the bottom of the screen.

One user may want to delete or reset a counter. These two tasks are not primary but are necessary anyway. They are also critical so a user mustn't do one of them by mistake. A good way to ensure that is to hide them: they will be displayed, only for a few seconds, after taping a counter (like in the built-in Photos app). The interface is also clearer most of the time. These actions can be undone by shaking the iPhone.

Finally, you can scroll through your counters horizontally. The most recent counter is on the right and you can pull to add a new one. It is possible to name a counter but we gave them a random name so you can do so afterward. A new counter's color is chosen randomly.

Here is the final result :)

We believe +1 is the ideal counting app for the iPhone. Some apps allow users to comment each incrementation, display dates and full descriptions. This is only noise distracting users. When you design a software you must make choices and keep focused on the essential.

Of course some points could be improved such as the iPad version.

+1 shows that designing a good interface has nothing to do with graphics. Designing an interface is identifying the tasks and organizing them accordingly to the context of use (in that case a handled device used with one hand).
April 18, 2013