I wanted to make sure I clearly address these comments, one of the issues in reading a post like this in an online thread is the most upvoted post can also be the most incorrect, and misleading.

#1 > The "security" of this device is a joke, just look at how randomness is derived:

Unfortunately, this commenter posted this without reviewing any of the security documentation available for OnlyKey. Had they reviewed they would see that we specifically address how analog input alone is not sufficient entropy for a cryptographically secure number generator and one of the unique features used with OnlyKey is using capacitive touch input for our RNG. This random input is generated every time you touch a button on OnlyKey, it's different for every person, and its truly random. https://docs.crp.to/security.html#cryptographically-secure-r...

#2 > Meaning that there is no hardware security whatsoever and it's trivial to extract all your keys from the device if you ever lose it. Whoops.

Again, had the commenter taken the time to read a bit they would see that this is completely false. As others have already mentioned, OnlyKey is not an Arduino, OnlyKey uses some of the great Arduino software libraries that are available open source and the Arduino IDE. This is completely unrelated to hardware. As for the OnlyKey hardware security we use Freescale Kinetis flash security to securely lock data on the key. As for side channel attack countermeasures we list several that are in use. For full details read this - https://docs.crp.to/security.html#hardware-security

When it comes to security questions, trust an expert, not the top post on a thread. For more information about CryptoTrust, the makers of OnlyKey you can find our team with internationally recognized security credentials here - https://crp.to/t/

For more info on OnlyKey:

Get started - https://onlykey.io/start

General documentation - https://docs.crp.to/

FAQs - https://docs.crp.to/faq.html

Compare to Yubikey - https://crp.to/p/

Setup and User's Guide - https://docs.crp.to/usersguide.html

Features - https://docs.crp.to/features.html

Support - https://forum.onlykey.io/

List of supported services - https://onlykey.io/pages/works-with-onlykey