If you read Tobii's forums, it's obvious that the EyeX developers are primarily focused on game integration. That's completely fair, since the company markets the tracker as a gaming peripheral, after all. I'm guessing Tobii also doesn't want to cut into the profits of its lucrative medical device division by giving too many capabilities to such an affordable device, either.
The EyeX currently supports 30 different games, from triple-A titles like Tom's Clancy's The Division to what are basically tech-demos showing off the potential of the hardware. My game of choice, DayZ, is somewhere in-between. The game implements a Tobii feature called Infinite Screen Extension that essentially hands over control of a point-of-view hat switch to your eyes. Since looking around only moves what you're looking at and not what you're aiming at, my specific problems with eye tracking are mitigated somewhat. Looking around in a game world doesn't require super-high eye tracking precision.
A common problem I ran into with the EyeX is that it has a harder time tracking when the user is looking at the left and right edges of the screen. That problem was especially true for me, but other people I roped into testing the device noticed it, as well. That can be a problem outside of games, where we'd expect uniform behavior across the entire desktop. It's not so big a deal in-game, though. If you look at something on the edge of the screen, the camera naturally brings that focal point to the center of the display where the tracking is better. I found that adjusting my view this way felt quite natural.
The Tobii software lets owners fiddle with per-game eye-tracking settings in its menus, but I was fairly happy with the defaults. The EyeX even worked well with DayZ on my 34" curved screen. Among other things, DayZ is a game about atmosphere and situational awareness, and I really think that the EyeX contributes positively to both. I would expect that other Bohemia Interactive games would benefit from the EyeX, too.
After testing out DayZ, I tried two of the games that Tobii offers on its own app store. The first was Beatshot, and I quite enjoyed it. It's more of a proof-of-concept than a game, but it'd hold its own against a classic like Audiosurf if it was fleshed out more. The game shows patterns of targets in tandem with some music, and you need to look at the targets in time with the rhythm of the music to score. As it stands, the canned one-minute demo is fun to show off and run through a few times, but that's about it. Someone take this idea and run with it, please.
The other game I tried was Spectrophobia. In this game, you play as a small girl who's ended up in a scary generic dungeon. This title uses more traditional keyboard-and-mouse controls. There are some items in the world that you can only interact with by looking at them using the EyeX, though, and parts of the dungeon that you can only see if you look in the reflection of a mirror. By looking at specific symbols, I was able to turn my harmless gaze into a fiery attack while also using mirrors to light invisible torches that unlocked doors. Spectrophobia felt interesting, if a little contrived.
I don't own Tom Clancy’s The Division, but based on my experience with the EyeX, I'm not sure I would trust it with the job of aiming my weapon or grenades. The "cover at gaze" function seems similarly prone to error. However, the map-scouting and enemy-tagging-related features seem like novel uses of of the hardware that would work pretty naturally and without much downside in the event of a glitch. I feel obligated to mention again that I might have more confidence in the more critical control functions if the EyeX didn't hate my face.
For what it's worth, Editor-in-Chief Jeff Kampman tried out the EyeX at CES with another Ubisoft title, Assassin's Creed Syndicate. That game implements enemy-tagging and grapple-point-selection features using the EyeX. He found the Tobii controller added a somewhat more immersive way of interacting with Syndicate's game world, even if it wasn't a revolutionary one. If you really like Ubisoft games, that developer seems to have a tight relationship with Tobii. An EyeX might be a worthy investment if you're looking for neat new ways of enjoying those titles.
You'll recall from my section on using the EyeX on a desktop that it seemed like some logical functionality was artificially limited in the software. I think that's a shame, but I also understand why that's the case. Tobii does make hardware and software under its Dynavox brand that is intended for use by people with limited communication skills. As medical devices, the prices for those products start in the thousands or tens of thousands of dollars, and they're likely only attainable if an insurance company can be convinced one is necessary.
The EyeX, on the other hand, retails for $140, and it's pretty easy to find YouTubers with coupon codes that lower the price to just $100. That makes it a pretty reasonable proposition if assisted or augmented communication methods are on your radar. You need the other half of the equation in the form of software to communicate with the EyeX, though, and that's where Gazespeaker comes in. Gazespeaker is designed for use with a number of eye and head tracking devices. It includes many features such as visual communication grids, text-to-speech functions, an email client, a web browser, a media player, and even a file explorer. It's a pretty impressive piece of software, considering it's available for free.
Taken together, the EyeX and Gazespeaker form a potent and affordable duo. I tested the combination out myself, and it performed admirably. I credit this to the secondary tier of calibration that Gazespeaker performs in-app, as well as the simple nature of the program itself. Fortunately, you don't have to rely solely on my experience here, because a member of our household is exactly the right person to really put the combo though its paces.
Our daughter, Ellie, has Cornelia de Lange Syndrome and most of the symptoms associated with it. She's far from your average three-year-old, to be sure, but generally speaking she's a very happy girl these days. Her primary qualifications as my co-reviewer are the trach she's had since she was two months old and her limb differences that prevent her from using a traditional input device (her friends affectionately refer to them as "t-rex" arms). The trach also prevents her from vocalizing, for the most part. Developmentally, Ellie does not act her age, but she is clearly capable of learning and she shows off new tricks all the time. She even started school recently, and we expect to be amazed and terrified by what she learns there, just like all parents.
I had no delusions about putting Ellie in front of the EyeX and Gazespeaker for the first time, though. It's tough to convince her to pay attention to anything that isn't My Little Pony or Curious George, but she has always liked lights and screens (that's my girl!) so I was excited to get an idea of what she would focus on with the EyeX. After humoring me for about 15 minutes, Ellie made it clear she was done with her first session. What we saw in those 15 minutes was intriguing, though.
Because we carefully positioned Ellie at the right distance and angle, the EyeX was able to do a fairly decent job of tracking her eye movements. We don't call her a crazy baby without reason, though, and her gaze moved all over the place no matter what we tried to show her within Gazespeaker—save for one exception. The red circle in the center of Japan's flag consistently held her gaze long enough to change the language of the program to Japanese. That might not seem like a big deal, but since Ellie's differences leave us, as parents, with a reduced ability to understand her preferences and abilities (especially mentally), any insight we can get is valuable. Because of Gazespeaker, the EyeX will continue to be used in our house long after this review is over.
Reviewing the Tobii EyeX was educational, to say the least. I find myself in the unenviable position of having reasons to both enthusiastically recommend it and suggest you pass on it for now. Unfortunately, my most positive and most negative feelings about it are both highly specific to my circumstances. If I remove my unique problems with the device from the equation and focus on whether the EyeX delivers on what it claims to do, it is safe to say that, yes, it does. Whether the EyeX's $140 price tag is worth it to you will depend heavily on your stable of favorite games and the features that the EyeX enables within them.
I'm fairly confident that the EyeX is only the beginning of the road for mainstream uses of eye-tracking tech, though. Anyone following VR news knows that foveated rendering is a hot topic and a likely method for improving VR quality without requiring 1,000x improvements in graphics-rendering power. That method only works if your PC always knows exactly what you are looking at. Given that requirement, it wouldn't surprise me if some form of eye-tracking ended up looking back at us in the future. For now, the EyeX remains an interesting curiosity that's full of promise but a little short on delivery.