GPS navigation and display other devices on the map. How to implement?

Question

Android

It is necessary to implement such a thing on androide: the user downloads the application, registers, in the gps application navigation on the city map (2gis? Google? Yandex?) Plus, you need to display all other customers on this map and their location on it. you also need to be able to interact with them, for example, click on the icon of another client on the map, a menu of what to do with it opens. Question: what to use for navigation, where there are such api so that you can implement this?

Answer 1

what is the api? here from the navigation system it is only required to get the position of the smartphone.
all other features you will need to implement yourself.
store positions of other clients on the server.
handle interaction requests between clients.
a normal multi-user application comes out,
you can give the interaction between the clients themselves to the mercy of peer2peer (this is if there can be no cheats)

Answer 2

However, there is a ready-made solution quickblox.com/developers/SimpleSample-location_use...