The only mobile gaming controller you need

Mobile gaming controllers are less of a luxury and more of a necessity as modern mobile games become more sophisticated and demanding. Whether you’re on one of the best gaming smartphones or your trusty tablet, simply tapping on the screen like an over-eager toddler only gets you so far.

Fortunately, a decent mobile gaming controller will only set you back around $100, if not less. The GameSir X4 Aileron is one of the newest options and promises an ultra-low-latency connection, e-sports caliber controls, and a new design that breaks free of the bracket-backed form factor, leaving room for external coolers, wireless chargers, and unparalleled portability.

Price, availability, and specs

GameSir’s X4 Aileron mobile gaming controller can be yours for $100. You’ll find it in various places online, including Aliexpress, but your best bets are likely Amazon and the GameSir official site, where it’s currently discounted by $10.

What’s good about the GameSir X4 Aileron?

Clicky keys, RGBs, and a snazzy portable design

Some may regard GameSir as a purveyor of budget-level peripherals, but I’ve been impressed by the build and quality of the brand’s products time and time again. The X4 Aileron is no exception. The rounded profile is unabashedly reminiscent of Xbox controllers, and the two pieces snap together via a series of strong magnets to make storage, traveling, and charging easier. There is a Hall effect joystick and microswitch D-pad on the left-hand piece. The right side bears another Hall stick and microswitch ABXY keys, which emit a delightfully mouse-like clicky noise, the staccato of which I much prefer over the subdued thock of standard Xbox controllers.

You’ll never have to worry about scratching or smudging the controller in a backpack. The X4 Aileron comes with a quality, hard-shelled carrying case, as well as modular swaps for the controls and a few other accessories.

Connecting the X4 Aileron to your Android phone (sorry, Apple users, this one isn’t compatible with iPhones) is easy. After a standard Bluetooth setup, the X4 Aileron will automatically connect when the clamping clip on either half slides up. This mobile controller fits a decent phone spectrum, accommodating devices between roughly 2.7 and 3.75 inches in width. Unlike controllers, such as the Backbone One, the X4 adopts a bracketless concept, which means you can fit wireless chargers or external cooling devices on the phone if you’re that serious about things.

I tested the X4 Aileron on a long list of titles and platforms. I flitted through several Xbox Game Pass offerings, including a racing game, a platformer, a FPS, and a couple of action RPGs. (It’s worth pointing out that an X4 Aileron purchase comes with a month of Game Pass Ultimate.) A couple more games were played via Steam Connect, and I wrapped up testing with some Android mobile games.

V-Touch is a notable X4 Aileron feature; it means only one of the controller halves Á la Nintendo Switch Joy-Con and the on-screen touch controls on the other side can be used. You can then map your preferred touch controls to the side without a controller and enjoy a hybrid play style.

What’s bad about the GameSir X4 Aileron?

Other options rely on your phone’s power instead of a battery

A few absent features make the X4 Aileron an odd choice over other mobile controllers. The controller’s clamping approach to holding phones in place seemed secure with most models I tested, but the smallest phone I used, a Motorola, felt a tad wobbly in the controller’s jaws.

Phones also can’t be charged through the controller, a feature widely offered by competing models like the Razer Kishi and Backbone One. And while GameSir’s FAQ on the X4 Aileron says that the controller will “work smoothly” while charging, this doesn’t make sense. The controllers must be snapped together to charge together, and only one half of the duo has the USB-C charging port, so even if you did plug the controller in while playing, you’d end up with one dead controller half and one fully juiced.

The X4 Aileron battery life is respectable, falling between five and seven hours depending on use. We have a lot of battery levels to keep track of, though. If you (and your charging station) don’t have the capacity for another cable or another frustratingly dead device, consider other options. GameSir has the G8 Galileo, a mobile controller that draws on your phone’s battery instead of its own.

The right product depends on its owner. And I’d prefer not to keep tabs on another battery, especially since the X4 Aileron doesn’t have any sort of sleep mode, which means you must remove the controllers at the end of your gaming session otherwise they’ll remain constantly on. (I have a phone dedicated to mobile gaming and left the X4 Aileron on the phone overnight. Upon picking it up the next day, I found the controller dead as a doornail.)

Lastly, the X4 Aileron is unfortunately not phone case friendly if the device is larger or has a bulkier case. Two of my three test phones were caseless, but my Google Pixel’s silicone case had to be removed to fit in the Aileron’s jaws. Even beyond phone cases, adding a way to adapt the Aileron to larger devices like tablets would significantly expand its reach.

Should you buy it?

A few compromises, but still a joyful (and niche) experience

As more mobile controllers surface (a handful from GameSir alone), convenience and performance remain at the top of my priority list when choosing one to toss in my bag for a road trip or casual afternoon of gaming. The GameSir X4 Aileron performs well, with delightfully clicky ABXY keys and a smooth, low-latency Bluetooth connection. The RGB accents are a classically gamer aesthetic, and the GameSir app opens up customization options for both the lights and controls.

The X4 Aileron is Xbox Game Pass optimized, and while it worked well with the other mobile games or Steam Connect games I tested, the greatest ease of use is reserved for Game Pass players, where the controls are smoothest and require the least amount of tweaking. You’ll need to check in on the X4 Aileron’s battery life after every gaming session, or just drop it on the charger every couple of days so you’re not surprised by an empty tank.

All in all, the ideal X4 Aileron user is very specific: someone who mostly plays via Xbox Game Pass and sees significant value in having room for an external cooling agent or wireless phone charger. An asking price of $100 for a well-built, powerful, snappily responsive mobile controller isn’t unreasonable, but the competitive edge of the X4 Aileron may be sharper to some than others.