The really hard part is conflict resolution. You updated something 5 times while offline, but another user deleted that something between updates 2 and 3, or ma

The really hard part is conflict resolution. You updated something 5 times while offline, but another user deleted that something between updates 2 and 3, or made a divergent update of their own. There are so many potential scenarios like this in a multi-user app. It's a huge rabbit hole, and you can end up in situations where it's impossible to sync in a user-friendly way. Essentially you are taking on all the challenges of distributed databases. Maybe it's worth it, but you should know what you're getting into.