In more recent versions of the Oppia app, users are able to see their placing/ranking (in terms of the number of points they’ve obtained) against other users on the same Oppia server.
This will work OK when users are regularly connected to the internet and so submitting their activities regularly, and have a data/wifi connection - as then their ranking will be quite up to date.
However in almost fully offline environments the leaderboard will not be up to date. It could be shared by exporting the latest version from the server and synching this (via the bluetooth transfer), but, to me at least, it only makes sense to do this if the bluetooth sync is happening very regularly - for example the leaderboard info is going to be misleading if it’s only updated every (say) 4 months.
Another issue to consider here is with an Oppia server with a lot of users and how useful it might be to know that you are ranked (eg) 2567 out of 3500 users. A better approach here may be to have separate leaderboards for groups of (eg) 50 users.
Any thoughts/suggestions etc on this are very welcome,