I've tried using it over the years but I never liked it because there was no information. So last night I looked at my local city and there is almost no information at all. I spent a few hours last night adding buildings and restaurants and removing incorrect items. It was actually kind of fun and therapeutic and I plan to do more of it tonight. My girlfriend thinks it's dumb and I'm wasting my time because Google maps and Apple maps and Bing maps exists but she just doesn't understand open source.
Edit: Apologies, I just realized this question is not Linux specific.
I use OsmAnd~. Mainly to analyze my skating routes (average speed, distance, etc) and planning sightseeing routes when on vacation.
For finding commute an app from local public transport is still the best and google maps are better than osmand, but for navigation on foot it's very good. And you can download the region earlier, so when you use it, you don't need that much data.
OSMAnd is how I use OpenStreetMap too. It's quite good for road routes even in rural areas, but especially in those rural areas finding specific locations can be spotty or outdated. Even in my town of over 100,000, I still have trouble finding some local places like restaurants and businesses. I always try searching for what I'm looking for before I leave home, so I have access to my computer to pull up a map and address to pin onto OSMAnd if I need to. (I'm someone who de-Googles as much as humanly possible so I don't use Google Maps.) With more up-to-date data it can be a great alternative to Google or Apple Maps, but that's the nature of crowd built data: it's only as up-to-date as the data contributors provide, and that's both a strength and a weakness of OSM.
In ideal world it would be businesses putting info about them in OSM, same as they do with Google maps now.
Until then it has to be us putting them on the map, I guess