You might never get to buy this amazing iPad keyboard [Review]


Sentis Libra iPad keyboard with trackpad
An iPad Pro with Sentis Libra attached could be mistaken for a MacBook.
Photo: Ed Hardy/Cult of Mac

The Sentis Libra gives an iPad Pro a keyboard and trackpad, allowing it to act as both a tablet and a laptop — something no MacBook can do.

However, rival keyboard maker Brydge accuses Sentis of using its patented design. Cult of Mac has both a Libra prototype and the most recent Brydge Pro, and we compare the two and let everyone judge whether the accusations made against this device stand up.

The Libra is undoubtedly great, including a highly-functional trackpad. So the real question is, who deserves credit for the design?

Sentis Libra vs. Brydge Pro

The Sentis Libra is a keyboard that attaches to one edge of an iPad Pro. It does so with a clip that also serves as a hinge. The clip/hinge works very well, securely holding the iPad while also making it part of a clamshell.

Trouble is, Brydge says it has a patent on this design. It’s used something very similar since 2012, and the company filed a patent-infringement lawsuit against Sentis.

The Libra prototype sent to Cult of Mac demonstrates how close this clip/hinge design is to the Brydge Pro released earlier this year.

Sentis Libra next to Brydge Pro
The first version of the Sentis Libra (on the left) is very similar to the Brydge Pro (on the right).
Photo: Ed Hardy/Cult of Mac

Sentis responded to the lawsuit by apologizing and redesigning this portion of its add-in keyboard. Instead of two separate clip/hinges, there’s a single one that extends across one edge of its product. We don’t have a redesigned unit, so we have to depend on images.

Sentis Libra version 2
The redesigned version of the Sentis Libra, seen here from the back and then the front, has a single large hinge.
Photo: Sentis

Brydge isn’t satisfied and is continuing its patent-infringement lawsuit. Nevertheless, Sentris remains confident it will be able to ship the Libra keyboard on schedule in January.

Sentis Libra trackpad

The feature that sets the Libra apart from the Brydge Pro is the built-in trackpad. No previous add-on iPad keyboard has one of these because iOS didn’t support them. However, the just-released iPadOS does.

Clip-on keyboards are popular among those who enter a great deal of text into an iPad (like a significant percentage the Cult of Mac staff). But reaching over the keyboard to the tablet’s touchscreen can get wearisome, especially for people who are accustomed to using a trackpad. The Libra gives an iPad users what they’ve wanted: a trackpad.

Our tests with the prototype unit provided by Sentis show that this feature works well. It’s 4.0 inches by 3.4 in., with left and right buttons integrated into the bottom edge. The trackpad is as sensitive as any MacBook one.

As mentioned, the actual functionality comes from iPadOS, and it reflects that an iPad is designed to be controlled by a fingertip, which is slightly different from how a mouse pointer works. The differences aren’t dramatic, but take some getting used to. Read this Cult of Mac guide on how to make the most of iPad mouse buttons to learn more.

Of course, Sentis wasn’t the first to come up with the idea of adding a trackpad to an iPad Pro clip-on keyboard; people have wanted one for years. And Brydge showed off a concept design last November, and will release this device early in 2020. The original version of the Libra looks quite similar to that Brydge concept from last year, which is why Sentis was hit with a patent-infringement lawsuit.

Sentis Libra iPad keyboard with trackpad
The Libra’s keyboard and trackpad could be from any laptop, but it’s for an iPad.
Photo: Ed Hardy/Cult of Mac

Sentis Libra keyboard

The actual keyboard in the Libra is 10.25 inches wide by 3.7 in. tall. Each key is 0.6 in. square, with 0.1 in. of separation and a decent amount of key travel. What all those numbers mean is this keyboard is about the size of the one in a typical laptop, and is as comfortable to use.

Backlighting makes it easy to type in low-light situations, and Sentis built in multimedia controls, as well as other iPadOS function keys.

Libra’s is a keyboard very similar to the ones in most of its rivals, including the Brydge Pro.

Sentis Libra hardware

The entire Sentis Libra is 11.1 inches wide, 8.5 in. tall and 0.4 in thick, not counting the hinge/clamps. That matches the front of a 12.9-inch iPad Pro.

The accessory weighs in at 1.6 pounds. The Libra converts the tablet into a clamshell so it has to be heavy enough to support the display when it leans backward. A lighter design wouldn’t have worked.

The Bluetooth keyboard is powered by a battery, which is charged through a USB-C port on the left edge. In a handy feature not included in any Brydge keyboard, there’s a second USB-C port on the right edge that allows the Libra’s internal battery to recharge the iPad.

This clip-on keyboard protects the front of the tablet, but the back would be left exposed except Sentris provides a cover. Even better, this folds into a stand so the iPad can be more easily used without the keyboard attached.

Sentis Libra cover/stand
The Libra’s back cover does double duty as a stand.
Photo: Ed Hardy/Cult of Mac

Sentis Libra final thoughts

We’re not patent experts and can‘t say definitively whether the redesigned Sentis Libra violates Brydge’s intellectual property, as Brydge says it does.

We are experts on iPad accessories though, and the Libra has a great design. Building a trackpad into a clip-on keyboard is something iPad users have dreamed of since 2010 when Apple launched its first tablet, and this accessory is what people have been hoping for.

But it’s impossible to ignore the patent-infringement lawsuit hanging over the Libra. Brydge is going to do everything in its power to keep this product from being released.

If that happens, it won‘t be the end of the matter because Brydge will release its own iPad Pro clip-on keyboard with a trackpad in Q1 2020.


The Sentis Libra is available on Kickstarter until November 8. The early-bird special is $109, and delivery is scheduled for January.

The current version of the Brydge Pro for the 12.9-inch iPad Pro, without a trackpad, is $169.99. The price for the one with a built-in trackpad has not yet been announced, but a release is expected in early 2020.

Sentis provided Cult of Mac with a test unit for this article. See our reviews policy for more information, and check out more of our in-depth reviews.