Offline and multiple devices
What works without a connection and how changes sync.
Check-ins, edits, archiving and deleting work without a connection. They show right away and sync when you're back online; a small mark shows what's still waiting.
Adding a new habit needs a connection, so we can check your plan and that the name isn't already used.
Two phones
Sign in with the same account on both. If you check in the same habit on both phones, you'll still have a single check-in. If you edit the same habit on both while offline, we'll ask which version to keep.