Graphhopper SDK for indoor turn by turn navigation

We are evaluating a potential project opportunity and the need is a turn-by-turn navigation for indoor navigation on Android platform with the following details:-

  1. Option to load an indoor map of a floor.
  2. Turn by turn navigation with shortest path from source PoI (Point of Interest) to Destination PoI markings on the loaded map.
  3. Arrows indicating directions.
  4. Distance to next turn.
  5. Prompts to user if he misses the path that needs to be traversed as per (2) above.
  6. Voice prompt (good to have).
    Is there a SDK and sample application to start leveraging it? Is this covered under the open source license?
    Sandeep Suresh.