OSM editing plugin allows you to make contributions to OpenStreetMap, a global community aimed at creating a comprehensive map of the world and providing up-to date open-source data to every user.
Just launch OsmAnd Maps & Navigation app and update the information about different locations.
How to use
Menu → Plugins → OpenStreetMap editing → 
→ Enable.
The plugin lets you create new objects, so-called points of interest or POI on the map. New shop opened next to you? Add it to the map! Your favorite monument is missing on the map? Put it there in seconds. Also, if you're the owner of a newly-opened business, adding it to the map is a great way to let people find you.
How to enable
Go to Menu → Plugins → OpenStreetMap editing → → Enable..
How to add POI
Tap on the map where the new POI has to be placed. Press on Actions, then choose Create POI, add its name and other details like working hours, website, etc. You'll also have to register at OpenStreetMap.org and then provide your OSM credentials to introduce changes.
How to upload GPX track
You can add the tracks you've made to OpenStreetMap.org. To do that, turn the Trip recording plugin on, record a track, and then go to My places-> Tracks-> press the 
button. Choose the required track and click Yes. You can change description, tags or visibility of the track.
Kindly note, that OSM editing has to be turned on. In an hour, your track will be added to https://www.openstreetmap.org/traces, so you can view it and other users can find it helpful, as well. You can participate in the work on the global map. Just share the tracks you've made. They become part of the OpenStreetMap.org project. Make sure you tag objects and roads as well.
How to report a mistake
You can also report about the mistakes on the map. All you have to do is tap on the location, choose Actions → Open OSM Note and then add the info about it. OSM editors would consider your comments.
To view the OSM editing layer, go to Menu → Configure map → OSM notes (online) → Enable. You'll see all the notes in the specific area. You can click to OSM note and choose your comment or delete it.