In this paper, we apply contextual mobile learning theories to our daily lives and professional situations. We designed a contextual mobile learning system based on IMERA (Mobile Interaction in Augmented Reality Environment) platform, with MOCOCO (Mobility, Contextualization, and Cooperation) features. We used RFID technologies to produce contextualization phases. CTTE (Concur Task Tree environment) tool was used for analyzing and modeling tasks. The contextual mobile learning system was applied in two case studies: (1) Computer Hardware Maintenance Scenario: we proposed a solution that uses mobile devices (Tablet PC or PDA) and augmented reality accessories (see-through Head Mounted Display) to provide just in time learning opportunities, when users experience difficulties in carrying out computer hardware maintenance tasks. (2) HSHB (Healthy Spirit in Healthy Body) project aimed at assisting people in selecting dishes in university refectory or self-service restaurants according to nutritional composition information and personal preferences offered by mobile devices like PDA or Smartphone. Primary experiments and evaluations were carried out in our laboratory. Usability and acceptability of system and devices together with efficiency and satisfaction of learning activity were assessed by questionnaire forms.