This one is a bit pricey but it necessary if one still has an older ipad without USB-C. It works well. Apple has finally made their ipad USB-C port compatible with yubikey, I haven't tested that. I have used this key with windows and Mac PC's, as well as with an iphone and it works easily and well. I also own a USB-C NFC and that also works easily, except with an old ipad. You need to have at least 2 keys in case one gets lost, and I recommend that the second key be a cheaper version as you don't need a complete drop-in replacement you just need the backup key to add a replacement key.
You should know that using a security key to lock down an apple account means that you lose the ability to ask Apple to unlock your account should you lose your yubikey, which can be a big deal. Other accounts are not as strict and treat the yubikeys as just another second factor. This is a complicated product and I am enjoying getting to learn about using it. Yubico has great support materials on their website and good links to external sites for various accounts and services you might use their key with.
Since this version is pricey (about $25 more than the USB-C/NFC one), I would recommend only getting one of these, and then a cheaper different yubikey as a backup. The backup device is only necessary if the first gets lost, and once you replace the lost key you only need the backup on one device to do the task of adding the replacement key to all your accounts. This is a bit cumbersome but hopefully it'll get easier with time.
Last thing - this key has it's keyring hole in the center, which works surprisingly well; it sits on my keychain nicely even though I worried it wouldn't.
TL;DR - great product but security keys can be "dangerous" and are not for everyone. This one is pricey because it supports an edge use case (old ipads).
Edit to add—I also own a USC-C NFC version of yubikey, which is similar to this product but is cheaper. I wanted to add that the lightning/USB yubikey is my favorite form factor as it is much SMALLER and I also prefer the activation mechanism of pinching it instead of touching a metal front.
| Manufacturer | Yubico |
|---|---|
| Part Number | Y-291 |
| Item Weight | 0.106 ounces |
| Product Dimensions | 1.59 x 0.47 x 0.2 inches |
| Item model number | Y-291 |
| Is Discontinued By Manufacturer | No |
| Size | YubiKey 5Ci |
| Color | Black |
| Style | YubiKey 5Ci |
| Finish | Reinforced Fiberglass Material |
| Material | Fiberglass reinforced polymer |
| Shape | Rectangular |
| Item Package Quantity | 1 |
| Special Features | dual connectors for Lighting and USB-C ports |
| Included Components | 1 Yubico YubiKey 5Ci |
| Batteries Included? | No |
| Batteries Required? | No |
