Mobile users generally fall into one of two camps: hunters (who want to find a specific piece of information or do a specific task quickly) and gatherers (looking to browse around or fill time, and less concerned about a specific outcome).. If your audience are hunters,
focus on features which enable them to achieve tasks in the smallest number of steps and minimise any functionality which does not help them. If they are gatherers, look at ways to give them fast access to broad information, then identify ways to keep them in your app. In this way, it’s possible to please both, but do be wary of becoming a Jack of all trades – in some instances, you may have a better outcome by picking one type and sticking with it.
Remember the 80/20 rule
Generally, 80% of mobile users will use just 20% of its desktop counterparts functionality. If your service is already online, an easy way to ensure that you cater to this is to look at how your customers interact with your website (particularly your mobile customers) and identify what functionality is used most, then use that information to cut down your feature set and make sure this vital 20% is as easy and intuive to use as possible.
Focus on the tasks
Mobile users want to accomplish tasks, whether broad (like browsing news items) or specific (like checking flight times). Every function of your mobile site should be geared towards helping them to both identify and then complete their task. Mobile users tend to be time-poor, and the real estate you have to work with is very small – you can’t afford to waste time or space. Try to sense their intent, and aim to expose the (relevant!) possibilities available at each stage of the task to the user, so they can swiftly move through to completion yet easily react to uncovering content they weren’t expecting.
Keep it simple
Mobile users don’t expect to read an instruction manual. Brief prompts are fine, as are service- (rather than app-) specific explanations, but if you find yourself having to put a FAQ in your app, you’ve probably gone wrong somewhere. Bear in mind that mobile simply doesn’t have the space for the annotations used in web, so things like clear iconography are a great space saver. In the long run, the simpler the app, the better it will be. It will be easier and cheaper to support and update, and it will probably do what it is supposed to. Remember the mantra: feature rich, user poor.
Capture more than just touch input
Human-computer interaction can be described as a lossy process – at any time, the user is generating much more input than the interface is capturing. This data is both a function of the user, and a function of their environment and established behaviour patterns. This includes obvious things like sound and movement, but also more abstract concepts like location, proximity, environmental factors, social networks, and intent. Mobile devices – with a huge array of sensors and communication channels; more than just about any other device – are uniquely placed to capture more of this “ambient” data. Think about how you can improve your user experience with intelligent use of it; using data the user didn’t even realise they were giving off is a great way to create surprising, memorable and engrossing outcomes.
Design for interruption
The unfortunate by-product of mobile browsing that can go anywhere and do hundreds of things is that invariably, something is going to interrupt the user – either in real life, or from within the phone itself. By keeping your app simple and your interface clean, you help reduce the cognitive load on the user, making them less likely to need to disengage from your app to do other things. But also ensure that it’s easy to pick up from where they left off if they are ejected out of your experience by an incoming call or their bus arriving – save states, break larger tasks down into smaller chunks, and put context throughout.