Since the early days of smartphones, there has been a phenomenal increase in the quantity and quality of mobile applications. Most of these applications aim to answer one specific need (like SMS for messaging) but do not coordinate their execution as most of the time they are made by separate developers. Composing and coordinating these applications should increase their benefit especially if the end-user is involved in the composition task. In addition, the use of the user contextual information should make the execution of the composed application more adaptive. This paper introduces a mobile personal assistant that empowers users to define rules for context-aware application composition. Such rules should enable the cooperation of applications in order to invoke the right action at the appropriate situation. A simplified rule language based on natural language is used to specify the adaptation rules. In addition, this mobile assistant offers the possibility to involve users in resolving ambiguity that may be faced when interpreting such rules, in defining high-level context by tagging other users, objects or any events. Such assistant will. The implementation of this mobile assistant demonstrates how such approaches may facilitate the adoption of context-aware computing in everyday life