I've been using this for a few weeks and it's great. In addition to offline-first, it would be nice to be able to ask Colota: List my trips between date1 and date2 when I was near (ie within x meters from) point y.
I am planning to use this for a long time too, so an export/import data for when I change my phone would be nice. I see Export but not Import.
Also, being able to delete trips between date1 and date2 would be useful. Currently, you can delete 1-by-1 or recent trips only.
In addition to wifi, Bluetooth beacons would be good too.
Seeing the same SSIDs (eg in a cinema) might also mean you are not moving, but then how can you tell you are not sitting near another train passenger with their hotspot on?