We present an Android-based platform for incrementally presenting spoken route directions to guide pedestrians to destinations. Our approach makes heavy use of stored procedures and triggers in an underlying PostGIS spatial database. In fact most of the 'intelligence' of our prototype resides in database stored procedures and tables. As such it represents an example of a challenging real world case study for the use of persistent stored modules (PSM) in a complex mobility application. It also provides a platform to study performance tradeoffs for complex event processing over spatial data streams.