We select and review products independently. When you purchase through our links we may earn a commission. Learn more.

The YubiKey 5Ci Brings USB 2FA to Your iPhone…Kind Of

Rating: 8/10 ?
  • 1 - Absolute Hot Garbage
  • 2 - Sorta Lukewarm Garbage
  • 3 - Strongly Flawed Design
  • 4 - Some Pros, Lots Of Cons
  • 5 - Acceptably Imperfect
  • 6 - Good Enough to Buy On Sale
  • 7 - Great, But Not Best-In-Class
  • 8 - Fantastic, with Some Footnotes
  • 9 - Shut Up And Take My Money
  • 10 - Absolute Design Nirvana
Price: $70
The YubiKey 5Ci on the red iPhone XR.
Cameron Summerson / Review Geek

Yubico launches its new 5Ci YubiKey today, which features an iOS Lightning plug on one side (a first for any security key) and a USB-C on the other. This brings the extra protection of a USB security key to almost any device.

The key is an interesting and versatile option for anyone who wants to increase security on their most important accounts—and especially those who want a USB security option on iOS. Just don’t expect it to work on all apps across the board, yet.

Currently, only the following list of apps support the 5Ci on iOS:

The Brave browser also supports the 5Ci for certain websites, like Twitter, Github, Login.gov, Bitbucket.org, and 1Password.com. Yubico is working with other iOS developers and online service providers to bring additional 5Ci support, as well.

The YubiKey 5Ci connected to the iPhone XR.
Cameron Summerson / Review Geek

The USB-C side of the key, however, works with any browser or service on any OS that supports USB security keys. That means you can plug it directly into Windows, macOS, Chrome OS, Android, or any other device that has a USB-C port. It should also work flawlessly with any Works with YubiKey service. As USB-C is offered on more devices, the 5Ci will also become your only USB security key, across all devices.

Of course, it’s worth noting this isn’t the first USB security key to work with iOS—the YubiKey 5 NFC has worked on all NFC-equipped iOS devices since the iPhone 7. Considering that key also has a USB-A plug, it’s an equally versatile option when it comes to compatibility. There is, of course, the need for dongles on devices that don’t support USB-A inputs or NFC, which makes the 5Ci a better choice for people with multiple types of devices. If it only had NFC, it might be the perfect security key. Maybe in the next iteration.

The YubiKey 5Ci.
Cameron Summerson / Review Geek

While we’re talking about caveats, there’s another big one that must be mentioned: the USB-C plug does not currently work with iPad Pro devices. The reason for this is unclear, but hopefully, it’s something Pro users can expect in the future.

When it comes to using the YubiKey 5Ci, well, it’s as simple as using a security key. You have to add it to your specific accounts on another device, like a computer (with USB-C, of course). But after that, you can use it to log in to accounts on iOS. I tested it with Twitter on Brave, and it worked instantly and without any fuss.

Right now, the 5Ci is a bit ahead of its time, but it’s the sort of push necessary to get broader support for USB security keys on iOS. It’s up to developers to incorporate support for this feature into their apps and services, and hopefully, the 5Ci will encourage that. Support within Chrome and Safari would also be highly useful, especially as more sites enable support for security keys on iOS.

Rating: 8/10
Price: $70

Here’s What We Like

  • First USB security key with a Lightning connector
  • USB-C increases usefulness dramatically

And What We Don't

  • iOS app support is very limited right now
  • The USB-C port doesn't work on iPad Pros (yet)
  • USB keys, in general, are still cumbersome

Cameron Summerson Cameron Summerson
Cameron Summerson is Review Geek's former Editor in Cheif and first started writing for LifeSavvy Media in 2016. Cam's been covering technology for nearly a decade and has written over 4,000 articles and hundreds of product reviews in that time. He’s been published in print magazines and quoted as a smartphone expert in the New York Times. In 2021, Cam stepped away from Review Geek to join Esper as a managing Editor. Read Full Bio »