I use this quite a lot - even my kids like taking part, on walks around the neighbourhood. Unfortunately, the app has an outdated basemap. During the lockdown I've used other apps and the in-browser editor to trace new outlines of buildings in my relatives' neighbourhoods, thinking that this would then show up in StreetComplete, giving my relatives a nice activity for future walks (adding addresses, roof shapes and street details for the new buildings I'd drawn). However, the app rarely updates the basemap - so the new buildings still haven't shown up. Worse still, the app pretends they're there, floating ghostly address, roof shape etc questions over a seemingly blank background - but a but too densely for people to reliably know what building they'd be tagging. This is a little irritating/demotivating. It's an acknowledged issue on their GitHub - the problem is lack of resources to compile and serve the basemap. If anyone is sitting on idle server capacity and connectivity... Do volunteer!