Characteristics of mobile applications in terms of development, usage and investment process are highlighted; analysed from the point of view of the investor, target group and return on investment. Mobile applications are designed to record user behaviour and databases assembled during this process represents raw material for the reengineering process. Recording user behaviour is showcased in the context on an actual application. Indicator of user behaviour are defined and submitted for debate. Indicators are validated by using data from a real life application. A model that facilitates the user oriented reengineering process is build. An efficient way of determining the optimal period for triggering the reengineering process is submitted. View full paper here.