The alarm you can only stop by scanning
Something not working, or an idea? Email wtfu@kranz.au. Include your iPhone model and iOS version.
I slid to stop and it rang again.
That's the point. WTFU rings every 30 seconds (you can change this in Settings) until you scan, for up to an hour.
I lost my tag.
On the scanner, tap Lost it? and type your escape phrase. Then register a new code in Codes.
Which NFC tags work?
Almost any: NTAG stickers, key fobs, transit and building cards. WTFU reads the tag's ID and only writes to blank tags.
It didn't ring when I was away.
If you've set a home, WTFU skips alarms while you're away. Switch When away to Ring in Settings to change that.