NextCloud Notes is frustratingly broken for offline use. The UI bricks itself with its own error messages when it can't phone home to the server. Even notes which are marked in the app as "Make available offline" don't work offline!

The iOS applications also are quite poor. For example the home screen widget has never shown me any of my favorited items even though it should, I have many favorited items, it is fully synced when I'm on my home network, yet it says "no favorites".

Considering the size of NextCloud and how long they've been around I wish they would fully complete more of their offerings before launching a dozen new ones.