Editors' note: Parts of this review have been taken from an earlier review of the Kenu Airframe.
The minimally designed Kenu Airframe took advantage of a car's air vents, usually placed within easy reach of the driver, as a mounting point for smartphones. The new Airframe Plus is not much of a stretch, if you will pardon the pun, from the original mount, merely adding about a quarter-inch to the bracket width to accommodate larger phones.
The Airframe Plus consists of an expandable bracket with a four-point rubber grip on the back. At less than an ounce, it's easy to carry around, yet its plastic-and-metal construction give it a solid feel. In black, it will sit unobtrusively on the vents in most cars. Unlike suction-cup mounts, the grip for the Airframe Plus makes this vent mount very small and portable.
The bracket expands from a 2 1/4-inch interior width to 3 1/4-inches, fitting even a Samsung Galaxy Note 3. Rated for screens of up to 6 inches in diagonal measurement, it will not fit tablets such as the iPad Mini or Nexus 7.
The rubber grip on the back of the bracket twists to allow different mounting orientations and sticks out 1 inch behind the bracket. It tapers down from its 1/2-inch base to a 1/4-inch tip, so will fit vents with fins spaced a 1/4-inch on each side.
Slipping the Airframe onto a driver-side vent in a car, the grips fit firmly on one of the fins in the BMW X5 in which I tested it. Despite the stiff bracket spring, I was able to snap an iPhone 5 into place with one hand. The weight of the phone and mount immediately caused the vent to point downward, although I could still see the screen just fine.
Turning the grip on the back of the bracket takes so much force that trying to change the orientation of the phone by twisting it would have broken the car's vent. I found that it worked best to twist the grip before mounting it to the car. However, the four points of the grip make it easy to switch the phone between portrait and landscape mode by simply repositioning it on the vent.
The placement on the vent turned out to be very convenient when running navigation, and I could easily activate Siri for making music selections.
Trying to remove my phone from the mount with one hand, the tight bracket spring caused the whole mount to come off the vent, ultimately making the process a two-handed operation.
I tested the Airframe Plus in mild weather, so did not need to crank up the climate control. However, I think it might be advisable to close the vent to which the Airframe Plus is attached. Blasting heat or cold air right at your phone won't do it any favors.
At $30 in the US (UK pricing is unavailable at the time of this review), Kenu's Airframe Plus costs a bit more than other vent mounts that can be found online. I liked the vent mounting position, as it put my phone within easy reach. However, the tight bracket made removing my phone inconvenient, as I had to pull the mount off the phone then replace the mount on the vent.