[flusensieb]

Not google maps style questions, but it's quite easy to add POIs using OsmAnd.

You need an OpenStreetMap-account, then long tap on the place, "actions", "Create POI" - enter the name and the type (restaurant, wastebin, whatever...) and save it.

If you're used to it and know the categories it takes maybe 30 seconds to do it everytime you visit a new restaurant or to add a new shop when you're waiting for the bus.