In this paper, we share our experience of developing a personal informatics framework for Android based smartphones that leverages mobile sensing for capturing and visualizing individual's performance and well-being with the aim of promoting awareness, self-reflection and self-optimization among-st users. We first describe an application that integrates different hardware and software sensors in smartphones to collect sensorial and contextual information. Then, we develop lightweight, interactive visualizations that effectively summarize quantitative data related to users' behavior patterns and routines, thus, facilitating them in self-monitoring and reflection-after-action process. As a final step we deliver personalized feedback and behavior change interventions for promoting positive behavior changes amongst the users. We also discuss some important results attained from a pilot case study that leverages a prototype of this system for validating and analyzing the results