StreetComplete is an Android app which finds wrong, incomplete or extendable data in the user’s vicinity and provides them the tools to complete these easily and directly on site without having to use another editor.
Data issues are presented to the user as markers on a map (like with Mapdust for example). They can be solved by filling out a simple form to complete/correct the information. The user’s answer is then processed and directly uploaded into the OSM database in atomic commits in the name of the user’s OSM account. Since the app is meant to be used while out and about, it works offline and otherwise aims to be economic with data usage. Note: to use it offline first connect to the Internet and point it to the area of interest and leave it running. It has a cache whose size can be varied where it stores tiles of the area so to use it off-line and see the streets it must be used in this way. Cache is stored at disk – but Android system may decide to delete it (happens on phones without plenty of disk space available). Also, viewing location at one zoom level will not cache map for other zoom levels. It stores the answered quests and when an opportunity arises it will silently upload them to OSM. The top shows the number completed and the number still to be uploaded is shown by (+XX).
The app is aimed at users who do not know anything about OSM tagging schemes but still want to contribute to OpenStreetMap by surveying their neighbourhood (or other places). Because of the target group, the app only presents issues which are answerable very clearly by asking one simple question, and which involve very few false positives.
You can help to translate the user interface via POEditor
Suggestions and bug fixes via GitHub (see https://github.com/westnordost/StreetComplete/wiki/Adding-new-Quests-to-StreetComplete before proposing new quests)