thanks @slavino for notification on this topic. As Locus Map dev, I’ll just give you a quick info here.
From my quick reading, seems you are looking for replacement for offline MapView system. Not sure why you want to replace MapBox system, but from the free alternatives, this is currently most easy to achive with MapsForge library (that Locus Map use as well). Anyway there is still some work with map distribution etc.
Locus Map and it’s API are not! replacement for the map view. App only offers API for displaying and work with app data on the map. Locus Map is mainly about maps, so if you want and easy and quick solution how to get maps to more people, you may give it a try. It is possible to simply create a service on your side, that will every second send new list of points to the Locus Map (if is running) so users may see content on many of available maps etc etc.
I’m not advertising Locus Map here, maybe opposite: warn you in case, you are really searching only for replacement of the MapView system.
If there will be any questions, feel free to ask, I’ll gladly help ;).
PS: btw nice example how this works is LiveMap offered by add-on Geocaching4Locus (geocaches downloaded from internet and refreshed on the map when user moves with the map).