Are there any devices with a built-in QR code reader? Android and iOS require a download. Not to mention Windows and Mac.

Do you ask people to download a QR code reader on their devices so they can access your WiFi router? That's a bit too crazy, don't you think?

Latest iOS supports QR codes through a standard camera app, no extra app needed

A fun fact I recently discovered when bored and "3D Touching" every app on my phone: Twitter.app has a built in QR code reader. It works pretty well, but I'll concede it might still be crazy to presume guests have the Twitter app installed :-)

edit: oh wow, as sibling commenter points out: the camera app detects QR codes now. neat!

FWIW, 3D touching the Chrome icon also opens a QR Reader.

Afaik, the default camera app on most android installs can recognize/read qr codes.

Never seen one that does this, but I only ever saw a Samsung (from 2012 and 2013), Lenovo (2016), Xiaomi (2018) and Huawei (2018) because my girlfriend and I don't swap them out every other year (heck, not even every four years). I feel like friends might have mentioned it as well, as the topic of a good, FOSS QR code scanner came up a few times in some chats.

Huawei has it, but it's kind of hidden and only accessible from the lockscreen (wtf, right?).