ZANavi is an open-source offline navigation app for Android that is free to download and use and has zero in-app purchases.
Ranked in these QuestionsQuestion Ranking
Pro Anyone can use or share the code
It's licensed under GPL which make sit ope-source, where anyone can look at or use the code which allows for an open understanding of the app.
Pro Usability focused
The core of the app is designed around ease of use which makes it an intuitive app to use.
Con Limited maps
There are many missing maps from the database making for user limitation depending on the are one lives.