Write to contact@inthemeantime.app. A person reads it.
Say which iPhone and which iOS version, and what you expected to happen. That usually saves a round trip.
A number appears only once at least twenty people are in it. Below that the app says a sentence instead of a figure — the count exists, it is just too small to show without pointing at somebody. Some actions, like medication, are never counted with other people at all.
The tap is written to your phone immediately; the number needs a round trip to the server. Off the network, the tap is kept and sent later.
On the Today screen, yes — Settings → Buttons. On the Home Screen, add the widget a second time and choose different buttons for it: touch and hold the widget, then Edit Widget.
Undo is there for five seconds, on the card and on the widget. After that, open History and tap the entry to remove it.
Hold a button on the Today screen instead of tapping it, and choose when it actually happened — up to six hours back, today only.
Yes. Without it the app says "people on your clock" instead of naming a city. Nothing else changes, and coordinates never leave your phone either way.
If iCloud is on, sign in on the new phone with the same Apple ID and your buttons and dots arrive by themselves. Otherwise: Settings → Your data → Export everything, then Import from a file on the new phone. The same file can be read twice without counting anything twice.
In iOS Settings → your name → Subscriptions, like every other subscription. Everything in the free app stays free, and your dots stay yours either way.
That is worth an email. The app is built to show nothing rather than a count it cannot stand behind, so a figure that seems off is a bug worth chasing.