Issue:
I’ve been having this issue for a few app releases now.
Intermittently, swiping from left to right on the iOS app (for example in the transaction detail view) to return to the previous screen doesn’t work - nothing happens.
It’s not an issue in any other apps I use, and force quitting the app fixes it (temporarily).
Details to reproduce:
Intermittent issue
OS: 
iOS 15.3.1
Device: iPhone 12 Pro
App Version: 4.18.0
This bug is still present in the latest App Store version. It’s intermittent and requires a force quit of the app for the swipe to go back gesture to start working again.
iOS 15.5
iPhone 12 Pro
Monzo 4.31.0
Still have this bug - app now on 4.33.0
Not come across this at any time using both App Store and TestFlight version.
Could it be a phone issue?
Definitely not a phone issue - the problem doesn’t occur in any other app nor in any part of iOS.
I’m trying to replicate but unable to at any point.
Possibly force closing reaffirms your grip to your handset, meaning when you attempt again it works.
It’s an intermittent bug, so if you asked me to replicate it now I couldn’t either (after a force quit).
I’m not sure what you mean by this?
I was thinking depending how you held your phone, moving grip on the handset to swipe up to force close and then reopen again, possibly then works to swipe out.
It’s happened in the past for me, but not with Monzo by memory.
I’m only speculating what may be happening.
Ah ok, no it’s definitely not that. As I say the issue only occurs in the Monzo app, nowhere else, and no amount of swiping attempts from different places along the left edge works until the app is force quit. I think it’s safe to say it’s a bug and not to do with how I’m holding my phone.
This intermittent bug still persists in the latest app version
iOS 15.7.1
iPhone 12 Pro
Monzo 4.55.0
Force quitting the app resolves it for a while, as before.
This bug seems to be getting worse. May be a coincidence, but since enabling the new home screen overview in Labs I seem to have been having to force quit the app much more frequently due to keep temporarily resolving this bug.
I surely can’t be the only one experiencing this issue on the iOS app 
Since initially reporting the bug, I’ve reinstalled the app multiple times, and now have a new phone as well.
Also an issue but not a bug, is that swipe to go back is not actually implemented in all sections of the app, some screens require pressing the back button, so there isn’t a consistent experience with this iOS feature either.
iOS 16.2
Monzo 5.4.0
iPhone 14 Pro