When comparing OsmAnd Maps & Navigation vs Avenza Maps, the Slant community recommends OsmAnd Maps & Navigation for most people. In the question“What are the best Android offline map apps for outdoors/hiking?” OsmAnd Maps & Navigation is ranked 1st while Avenza Maps is ranked 5th. The most important reason people chose OsmAnd Maps & Navigation is:
[OSM] provides a map editable by everyone; just like the web-based encyclopedia, Wikipedia. Using a community edited map allows one to correct isses they encounter. Combined with the monthly turn around, these edits are added for navigation quickly. : http://www.openstreetmap.org/
Ranked in these QuestionsQuestion Ranking
Pro Based around crowdsourced OpenStreetMap data
OSM provides a map editable by everyone; just like the web-based encyclopedia, Wikipedia.
Using a community edited map allows one to correct isses they encounter. Combined with the monthly turn around, these edits are added for navigation quickly.
Pro Works offline once the maps are downloaded
Pro Routinely updated maps
Utilizing the community driven OpenStreetMap data has allowed for monthly publishing of new maps that the user can use. Though that doesn't necessarily mean the map data has changed.
Pro Excellent general map viewing
Sometimes one needs more than just navigation, they have a need to view a map or specify a specific route. OsmAnd provides a very nice, detailed map. This can be good for seeing what is around you or showing a place you are talking about to a friend.
It also provides a means to add waypoints on the map which can be used to dictate a specific route (not simple enough to do routinely).
Pro Contour lines enable understanding the terrain
Through the use of an additional plugin OsmAnd Maps & Navigation is able to utilize contour lines on its maps which helps view the landscape and terrain.
Pro Helpful lane guidance
Lane guidance can assist in deciding if one should stay in the right or left lanes. OsmAnd provides detailed information on the number of lanes and which are valid for your chosen destination; based on the data available it may show too many or too few lanes.
Pro OpenStreetMap contributing made convenient
One can also utilize features to contribute back to OSM. This includes reporting a bug or adding a POI. This feature doesn't require an internet connection as the points can be uploaded latter upon request.
Pro Shows speed limit
Pro Free and open source
Pro Very detailed official local maps
Supports official maps published by park services, etc, which often have more details than any other map available.
Pro Save placemarks
Pro Records GPS tracks
Con Poor navigation interface
The interface is not the most intuitive, though is continually progressing. It doesn't provide a 3D view like many navigation apps.
Con Slow rendering
It can take some time for an area to be rendered. This tends not to be a problem during navigation since only a small area must be rendered as the map moves, and this area isn't immediately needed; though likely a bigger issue with smaller screens.
Con No display when the next speed limit occurs
When driving on unknown streets you are often surprised by speed limits or town signs, so you have to friction brake.
Con Slow and sometimes poor search
Most often does not find what you are looking for (which is not caused by bad OSM data).
Con Terrible address data
This is a limitation of OSM's data, but it is unreliable for locating an address while offline. Even with internet it doesn't appear that it can locate most addresses.
Con Near impossible to scroll through map
Due to the slow rendering (already mentioned) it is near impossible to scroll through OsmAnd's maps. You move the map only slightly and it takes ages to redraw all vector layers.
Con Being based on OpenStreetMap data can be lacking
The use of OSM also has the drawback of many places not getting the attention needed for updates. Depending on the geographic location OSM may have the most detailed maps or the most bare/outdated map.
Con Map search is awful
Searching for map files is very frustrating as the map search only shows the center point of each map as a pin, so you can't see whether the map includes a point you're interested in, and since there are usually many historical maps of the same location, they produce many pins appearing on top of each other. You have to download each one and open it in order to see what it will look like, rather than previewing them in the live display. Good overview maps will appear as pins in random locations, while there will be tons of topo map tiles everywhere else
Con Only shows one map at a time.
It supports USGS topo maps, for instance, but if you walk off the edge of one, you have to manually load the adjacent map, which is a hassle. It would be nice if, like other apps, you could select "USGS topo" as the map source, and it would automatically show whichever specific map your location is currently near the middle of (since the USGS maps have margins and legends, etc.)
Con Only supports local maps
You need to plan ahead and download a map for each park or region you're going to visit before you go offline.