The dynamic study of pendulum systems is considered an indispensable subject for physics and mechanics students in colleges and high schools. In this paper, a detailed methodology is given concerning the use of smartphones in pedagogical practical work for studying the dynamics of pendulum systems. Whereas, three aspects have been discussed through three cases concerning the study of the oscillatory motion, trajectories, and the energy aspect. Besides, some recommendations were provided regarding the process of data acquisition and curve-fitting processing to mitigate measurement errors. Experimental results exhibit a good agreement with theoretical results regarding the period of motion, trajectories, and mechanical energy. This makes the smartphone highlights a real opportunity to be a useful instrument to perform an overall study of the pendulum systems, the thing that was impossible without the intervention of professional equipment.