Last year I had an influx of mobile projects and needed to find a way to carry out usability testing on a mobile device. I’ve been meaning to share my solution for a while, but it’s taken me until now to get round to it.
When it comes to carrying out mobile usability testing there’s a variety of well documented solutions, for example Harry Brignull’s usability testing sled made for a fiver, Nick Bowmast’s variation on a theme, and Lokion Interactives pimped sled beautifully monogramed and made by Ponoko. There’s also a great slide-deck from this years IA Summit which summarises the different approaches that can be taken, including the pros and cons of each.
What would MacGyver do?
At first I considered copying an existing solution, especially as there’s so many good ones already floating around. However, I had several requirements that I didn’t feel previous sleds had answered completely enough. I wanted to create a testing sled that was:
- Unobtrusive for the person using it – this isn’t easy by any means but I wanted to try and stay out of the way as much as possible, meaning the sled and camera had to be small, lightweight (light enough to hold in one hand) and have minimal impact on the participants field of vision.
- Of a professional standard – as I work in a commercial context the sled had to represent my client and agency in a professional way. I’ve seen some solutions that rely on Blu Tack or sticky-tape to hold them together, which is a perfectly fine solution but something I personally wanted to avoid.
- Adjustable and interchangeable – I wanted the ability to alter the camera position (to allow for lefties and righties) as well as accommodate multiple devices without too much fuss.
- Easily duplicated and disassembled – heading up a rapidly growing UX team at the time the rig had to be remade easily and consistently within a short time frame. To accommodate different devices and testing in multiple locations it had to be in kit form.
- Made from widely available parts – to allow for future duplication I wanted the rig to contain no expensive, limited edition or bespoke parts.
I shopped around for affordable parts that were readily available so I could make more in the future if everything went to plan, and if something went horribly wrong I could source replacement parts easily. I managed to get everything, including the camera, for a little under £42 (including postage). I used:
- Hue HD USB webcam
- A cheap flexible iPhone case
- 1.8m USB extension cable
- Black cable ties
- Adhesive Velcro patches*
* Initially I planned to use superglue, but instead opted for small adhesive Velcro patches so that it could be disassembled if necessary
The only tools used were a scalpel and a Sharpie (to mark where to cut), MacGyver would have been proud.
Making the sled
Firstly I had to attach the webcam to the case, in a way that wasn’t permanent but was secure and stable. The Hue HD webcam comes with a USB stand, but it wasn’t necessary as the USB on the camera could be plugged directly into the extension lead.
Four small cuts were made in the back of the iPhone case, the space between them equal to the width of the USB extension lead. Two cable ties were passed through, horizontally to the case, and left untied.
Then the USB lead was placed between the cable ties, which were tightened to secure the lead in place. A small square of adhesive Velcro was placed just above the USB port with the other half stuck to the webcam’s USB plug. This meant that once the webcam was attached to the USB port the Velcro held it in place and stopped it from moving around, or detaching under it’s own weight. Initially I was worried that the Velcro wouldn’t hold the weight of the camera but it actually worked well and was pretty solid. Finally the iPhone was clipped into the case.
The end result
The camera was attached so that it curved up from the bottom of the phone and therefore didn’t obstruct the users view too much, it also meant that the cameras built-in mic was close to their mouth. Once the camera was attached and the phone was in the holder the USB lead could be attached to a laptop, which in this instance was equipped with Morae testing software. By using Morae, we could position a second webcam (we used the laptops built-in webcam) to capture the participants facial expressions and body language.
It took a little bit of tweaking to get the camera positioned correctly so that it was in focus, and the webcam did add weight to the phone and unbalance things a little, but without hands on experience of other testing sleds I can’t say whether this was better or worse than other solutions. We also found that, if we didn’t get the position perfect, occasionally the camera was susceptible to wilting to the right or left but only very slightly and not to the extent that it was noticeable to the participant or detrimental to the recording.
That said for only £42 (not including the recording software license) and only taking 30 minutes to build from scratch I was really pleased with the end result. It was straight forward to adapt for other devices (e.g. iPad and Android devices) and very convenient to transport. I’d recommend it as a solution, and it definitely worked for me, but without trying out alternatives I couldn’t say how it compares.
If you have a go at recreating this sled I’d be really interested to hear about it, whether the experience is good or bad.