(as at August 2017; these are the best navigators I have found out of many on Play after extensive testing. Requirements: FREE, OFFLINE MAPS, GOOD FUNCTIONALITY)
I also tried Mapfactor which is listed at end.
Pros Functionally its roundabout entry and exit are clear and easy to understand. Reroute when online was best of all 3 maps here; fast reroute with no errant path.
Artwork of the GUI is outstanding. GUI is reasonably logical, however see Cons.
Cons TTS/voice is flakey and has been this way for years; changes from UK English to US English at random. Offline map method worst uses region downloads which will be removed after about 30 days. GUI user can get lost eg trying to find out how to save an area and other functions is sometimes not so intuitive. Reroute in offline mode seemed non-existent as at August 2017, as when I missed a turn navigation ceased to work or catch up on predefined route. Offline search is least effective.
Pros Functionally is the easiest app to use. The devs have done a great job of making this an easy, reliable offline mode free navigator. Searching results in a list of all streets of that name, and the suburb/district, making it easy to select the correct street out of several same name. Reroute attempt when offline is fast. Voice is clear and reliable, but intermittent. Has all modes of travel includes bus and taxi (see Cons).
Cons Traffic conditions did not seem to work well. Reroute was a tad aggressive insofar as wanting to keep you on original path even if you have deliberately altered course. Eventually it will reroute to consider the new path you have taken. Navigating screen is the least 'arty' of these maps. Route is shortest, not necessarily fastest.
When searching offline some destinations not found so you have to either zoom the area or switch online, which is not a problem, but there seems no switch in nav screen to turn offline again. EG seems you have to exit nav to switch offline? Missing zoom on turns eg roundabouts etc. Missing waypoints. Missing Bus itinerary (in New Zealand). Only way to save favourites is to set up a free account with herewego and then you can save a non-editable range of favourites. Voice buggy; sometimes audio at start the route, then it stops working. GPS buggy; loses GPS even though alternative navigator has no problem on same device same location.
Above search shows region Remuera (maps.me doesnt)
Pros GUI is beautiful, good use of colours and nice detail; visually better than HereweGo and as good as Googles. 2nd easiest to use. Clear voice. History and adding a place/favourite to map is best of all three apps. Categories is a great way to find local amenities. You can add a stop, and the app will reroute, which is possibly another way of adjusting for bad traffic re-routes (see Cons). Transport = car, bike, walk, taxi (no bus). They use OSM maps as data source and it's an open project that can be edited by everyone interested in. If a user knows details which are not specified on the map yet, he can add or edit information. These edits will become available for others in the next update of maps in the app (in theory).
Cons Search is limited. EG in NZ search for 'Seaview' gets about 10 results in Auckland, with no area region displayed. I needed to show Seaview road in Remuera. This can be overcome by searching for Remuera, zoom map, then search again but thats convoluted. A trick Ive found which is not consistent but if you search for area,road seems to work even if it says 'results not found' eg 'remuera,seaview road' then press Search. There is also a LIST button which gives points you can zoom to so they almost have it sorted.
There is NO overspeed warning.
If using traffic the engine can route you to a invalid route sometimes doubling the distance. By switching off traffic gives correct routing.
Unlike HereWeGo, in which you can avoid toll road, unpaved roads and various filters, maps.me has none such. This is the single most wanted missing feature IMHO.
Search results can confuse Original path without traffic (Edited) erroneous path doubled distance Beautiful maps.me nav screen
Functionally more complex than other apps but what ruined this app for me was its TSR (Terminate and Stay Resident kernel) unable to remove apart from uninstall.
While Mapfactor was installed both Maps.me and HereweGo voice/audio ceased to function. Removal of the app removed the kernel and voice worked again. This possibly is an issue unique to my Samsung Note 3 but I could not recommend app that installs a TSR anyway. Its map/navigator view is visually rudimentary, with jerky vehicle movement and low resolution.
HereweGo just works, and mostly works well, its just that visually its not so nice. If you need totally offline maps either maps.me or HereweGo are good choices, but if you can afford a little data use then Google Maps is the way to go (pun). Download Google Maps area maps over wifi before departing which keeps data use minimal. Google Maps running on data is best due to search and map functions, but if in patchy data areas, can make guidance unreliable.
Personally, maps.me is my preferred choice as we dont have too many toll roads in New Zealand and its interface/GUI is lovely. It also keeps getting better as time goes on.
If you have used any of these Android Navigators please leave a comment below as to your own experience thanks kindly.