Remember roaming charges? Neither do I. So I wasn't particularly thrilled, when a couple of hours into our weekend trip to Zürich, I hit the roaming ceiling (€60 wasted), and my carrier conveniently disabled mobile data. That caught me completely unprepared, and I would have been royally screwed if it weren't for Organic Maps. Actually, I had the app installed on my Android device for quite a while, but the force of habit kept me using Google Maps.
Deprived of a mobile data connection, I had no other option but to switch to Organic Maps. It turned out to be a blessing in disguise. Not only does the app work offline, it also lacks all the anti-features we all love to hate: ads, tracking, data collection, mandatory registration, etc. More important, Organic Maps is released under an open-source license, and the app uses Openstreetmap as its map data source.
I only had a day and a half to do real-world testing, but the results are more than encouraging. Two things that I appreciated from the get-go: apparently better routing compared to Google Maps and automatic re-routing. I used Google Maps to find our way from the central station to the hotel and Organic Maps to plot the return route. The latter proposed a slightly shorter and much simpler route. Needless to say, it's hardly enough to draw any conclusions, but it's worth a closer investigation.
Maybe I've been using Google Maps all wrong, but I never figured out how to make the app automatically adjust routing when I take a detour or choose a wrong turn. Organic Maps does this automatically (albeit with a slight delay), no tweaking required.
It's a matter of personal taste, but I prefer Organic Maps' map rendering: the 3-D buildings feature seems like a minor thing, but, for whatever reason, it makes reading the map easier.
You can bookmark places in Organic Maps, and you can organize bookmarks into lists. It's also possible to export and import bookmarks in the KML format. Speaking of bookmarking, the only feature that I miss is the ability to create KML bookmarks on a regular Linux machine. There is a desktop version of Organic Maps for Linux, which is great. But it provides no way to bookmark places. So I've devised an awkward workaround that involves saving places in Google Maps, then exporting them in the JSON format through Google Takeout, and then converting them to KML using the json2kml script. Needless to say, it's far from an ideal solution.
Obviously, these are just initial impressions, but there is a good chance that Organic Maps is going to replace Google Maps as my primary map tool. In any case, I'll be donating to the project and keeping a close eye on it.