GameSir’s X4 Aileron Bluetooth controller isn’t the best I’ve used, but it quickly became one of my most-used controllers.
The X4 features a two-piece design that easily collapses into a surprisingly portable little package. The pieces can slide onto the ends of your smartphone and it connects wirelessly, allowing it to work with both iPhones and Android devices. I used it exclusively with Android phones, but MobileSyrup’s head of creative Brad Bennett also tried it with iPhone, though he had some issues getting it to connect at first.
GameSir boasts the controller is designed for Xbox and it sports Xbox-style face buttons. It’s billed as a controller to use with Game Pass, but it also works fine with other mobile games in my testing. Other notable features include Hall Effect joysticks, anti-friction glide rings, additional L4 and R4 buttons on the back, and more. The X4 also comes with a carrying case and interchangeable parts so you can swap out the D-pad and joysticks based on your preferences.
What really set the X4 Aileron apart for me was the collapsability. Sliding the two halves of the controller together is extremely satisfying thanks to magnetic locking, but it’s also incredibly convenient for taking the X4 on the go — a main perk of mobile gaming. Sure, most mobile controllers are pretty small, but the X4 is wonderfully compact compared to options like Razer’s Kishi Ultra or even GameSir’s own G8 Galileo.
Of course, not everything about the X4 Aileron is perfect. For one, the compact size comes with some trade-offs in ergonomics. I found the placement of the right thumbstick wasn’t ideal, though it only bothered me when playing titles that required heavy use of it. Further, I can’t help but feel the design could be tweaked slightly to allow the X4 to be functional when the two halves are attached. The form factor results in the two halves being inverted when connected, which means you can’t use the X4 as a wireless controller this way. Perhaps the single biggest improvement GameSir could make (maybe with the X5 Aileron?) would be designing it to act as a real controller when the two halves are connected.
The X4’s magnets already let you connect it like this, why not go a step further to make it lock together securely?
The green bars sporting the ‘GameSir’ logo on the X4 double as both a really smart part of the controller and a small annoyance. These bars are part of the clamp system for attaching the controller to a smartphone, and honestly, what GameSir did with these is kind of smart — they double as power switches for each half of the X4 controller. When the clamps are extended, the controllers turn on and then they automatically turn off once there’s no tension on the clamps, allowing both sides to turn on and off simply as a part of putting your phone into the controller grips, saving users from fiddling with power switches on both sides. My one small gripe with it is having two big, green GameSir logos hovering above my phone screen is ugly, but it’s not that big of a deal breaker.
Users can manually turn on the controllers by holding down the Xbox button on the left side and the share button on the right side, which is handy if you want to use them without putting your phone in the clamps, or if you want to use another device like a tablet that won’t fit in the clamps at all.
My last small but notable complaint about the X4 Aileron design is that because there is no USB-C connector to plug the controller into my phone, I now have to worry about charging the controllers. To be fair, the battery life on them is quite good — in the roughly two months I’ve had the X4, I’ve only charged it a handful of times. Each side sports a 400mAh battery, but unfortunately, you can’t charge and play since there’s only one USB-C port, so you have to connect the two halves to charge them.
Overall, I really like the X4 Aileron, and it’s quickly become my most-used mobile controller thanks to its compactness. It’s easy to take with me when I leave the house, which goes a long way in making me use it more. I have a few small quibbles with the X4, but nothing that I think significantly detracts from the experience.
How to use the GameSir X4 on iPhone
The controller can be set in two different modes. By default, it connects as the ‘GameSir Aileron X4,’ but if you hold down the Xbox button + B the controller will switch to Xbox mode (Xinput). Once you do this, it will appear in your Bluetooth settings as an Xbox controller. Simply reconnect it, and then it will work on your iPhone. To Switch back to Aileron mode, hold the Xbox button + A.
The GameSir X4 Aileron is available in Canada on GameSir’s website for $141 or from Amazon for $129.99.
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