So for reasons I won’t get into, I have a faulty main camera on my Samsung Galaxy S III.
It turns out Snapchat still allows me to take pictures and save them without crashing, due to it having front camera on by default. But I found myself needing a barcode scanner or QR Code scanner for 2-Factor authentication.
Most barcode scanner apps, which automatically boot into scanning mode will just crash straight away. I spent quite a while trying poorly written bar code scanners (even the one Google Authenticator suggests) which just crash if the back camera is broken.
Eventually I found a solution. QuickMark Barcode Scanner doesn’t crash right away and allows you to switch to your front camera. It has a pretty decent UI, and they also have a pretty good Windows app for scanning barcodes on your screen. Good job on the developers for handling erroneous situations gracefully.