Great concept but do your research before buying This review relates specifically to the Yubikey 5Ci and the iPhone 14pro using IOS 17.1 in the UK. The 5Ci key doesn’t not have the NFC facility (contactless connection) therefore it has to be inserted into the lightening port. However it will not connect unless the case is removed before insertion. I appreciate cases vary but mine is a standard apple purchased case. (Rim thickness 1 or 2 mm!) Quite frankly in my view the inability to use NFC or the lightening port without removing the case renders the key impractical. This is not made clear when purchasing the key. Even if this is acceptable to you it seems that most financial / bank apps in the UK do not support the concept of the key yet. If you are inclined to buy the key it’s worth checking before hand that the services you wish to use support the Yubikey I purchased them (you need two) through Amazon and was given a refund. Yubikey were helpful up to a point but their support links are complex and cover a multitude of keys and devices. The concept is good perhaps things will improve.

UK customers - Beware the artificially high shipping fee I placed an order with Yubico. They charged EUR15 for shipping. My order was delivered by Royal Mail Tracked 24 service. According to the Royal Mail website, this cost Yubico GBP3.30 for an 80g shipment weight as declared on the Royal Mail label. This means Yubico have charged an artificially inflated price for shipping (GBP3.30 is EUR3.75, which is substancially less than EUR15)

I purchased 2 yubikey devices in May I purchased 2 yubikey devices in May, paid for express delivery, and still waiting for the devices to arrive at mine. I have tried to contact them via tweeter and emails but no headway so far

Absolute disaster Absolute disaster. Stay away. No customer service. Yubikey does not work well with Google Chrome and windows 10. I was locked out of all three of my crypto trading accounts after the first day with an error message on all three that said my device was not recognized by windows Chrome security and to try another key.

Non Existent Customer Service - Also Just Plain Rude Shockingly bad, full-friction customer journey. Customer Service is non-existent for all practical purposes including initial purchase. I wanted to spend 15 minutes buying these security keys - I'm at the end of day 2 now and still haven't made the freaking purchase due to non-existent help from Yubico and their so-called resellers in the UK. The resellers don't actually sell anything, they refer you on to someone else. If you want to get a freaking headache then please go ahead and start your journey with these unhelpful, rude, time-wasting, arrogant people.