In this series of blogs, I will describe the critical success factors that make or break a kiosk system – the things that determine whether the kiosks make money, or whether they are just a waste of space. For each characteristic, I will give examples of live kiosk systems that, in my opinion, have got it right.
The third factor I’d like to talk about is usability. Previously, I described how Kiosks must be well sited designed and signposted to attract users to them. So, let’s assume you’ve got users’ attention, how do you keep it? How do you make them feel engaged and confident in what they are doing?
Usability: the quality of being easy to use
Keep it Simple
Like websites, kiosk systems must be usable without any training. Yes, you can have help screens, but in practice most potential users will not have the patience to read them. They might be happy to stand and watch the previous user or to watch a short instructional video, but it is much better to make the system so simple that this is not necessary. People don’t like to appear foolish, and standing for too long at a kiosk doing nothing is likely to make them feel foolish. So let them get started quickly with simple choices from a short list. It is better to have more steps, each with a simple set of choices, than it is to have a few steps, each with a complicated choice.
Use very simple language and clear instructions. It is best to test the wording on people who know nothing about your system. You might be using terminology that isn’t generally understood or phrasing that can be misinterpreted. Illustrations or icons can be used to supplement the text. For example, when something like a credit card or photo memory card needs to be inserted, show the location of the slot and the correct orientation of the card using a picture or short video. This is also true for menu options.
Use Menu Screens
If the kiosk supports up to four basic tasks, then all four can be offered on the opening screen. But if it offers more than four functions, which is about the limit for a user to read and understand quickly, then I think it’s better to group the functions under common headings. By grouping functions, you can limit the choice on the first screen to no more than four things. The full range of functionality is then accessed via a second (or even third) set of menu screens.
Reassure and Entertain the User
If a process is going to take more than a few seconds, it’s worth reassuring the user that something is happening. If you don’t do this, the user may assume that the machine isn’t working and continue to press keys or touch the screen. A progress bar or spinning icon are a good way to do this. I can hear you say that this is just good practice for any user interface, but touch screens are particularly susceptible to unnecessary repeated input. Lack of feedback makes the user unsure about whether they touched the screen properly. An audible click or some visible change to the button helps, but the safest thing to do is to suspend all future input from the screen until the process is complete.
If a process is going to take several minutes, then take the opportunity to entertain the user with a video advertisement. However, you should resist the temptation to have the video take longer than the process. Many customers will be in a hurry and it is generally more profitable to have a rapid throughput of many customers than it is to keep a few customers longer than they would prefer.
Allow the User Privacy
I mentioned in Kiosk Success Factor #2 that it is important to give users enough space to use the kiosk. You should also take privacy into account when designing the user interface. For example, if they are selecting images to print from their digital camera, you should only show thumbnail images unless they specifically ask to enlarge a picture. They may not want bystanders to see their photos. An alternative approach is to use a privacy filter to blur the screen image when viewed from a wide angle.
Gain the Users Trust
If you want users to spend money at your kiosk, you need to gain their trust. People are naturally suspicious of technology. They may worry about entering their credit card or inputting their personal details. So you should only ask them to do this things after you have told them what they will receive in return and after you have reassured them about their privacy and security.
Usability is a big subject, and I’ve only covered a few basics here. If you’re going to put a big investment into kiosks, then you should get advice. A poorly designed user interface will kill your system – however good the kiosks look. The next blog in this series will deal with the closely related subject: “Accessibility”.
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Rental store giant Blockbuster has risen to the challenge by launching its own kiosks in the US. And now the concept has arrived in the UK. 
Nokia-branded kiosks are starting to appear in Carphone Warehouse stores in the UK. They are being used to promote their Pixie Lott Illuvial range of phone designs.