There are a number of QR code reader app on the App Store. Most QR codes are nothing more than a link to a website address, thus it is convenient if mobile browser has QR code support built right in. This would mean one less app on your iPhone.
Mobile Safari and Firefox do not support the scanning and reading of QR code. QR reading and scanning however are built-in feature for Chrome, Opera Mini, Puffin Browser and UC Browser.
For Opera Mini, the QR scanning option is available when you start typing in the address bar. Tap on the QR button on the keyboard toolbar to access the QR scanner.
For Puffin Browser the QR scanner button is conveniently located on the right end of the address bar.
Similar to Puffin Browser, the QR scanner button on UC Browser is located at the end of the address bar.
Chrome is not making its QR scanning feature obvious to use. You can not access it from within the app. Instead the QR option is available when you 3D Touch the Chrome icon on the home screen. On the 3D Touch menu that pops up, tap on “Scan QR Code”.
For those using an iPhone without 3D Touch, you can access Chrome’s QR scanner by using Spotlight search. On the home screen, pull down the Notifications screen or Search screen to access the Spotlight. Key in “qr” on the Spotlight search to let spotlight display the list of apps and documents with “qr” wording.
From the Spotlight result list, look for the Chrome icon with the text “Scan QR Code”. Tap on it will bring you directly to Chrome and launching the QR scanner.