Due to the widely spread mobile devices over the years, a low cost implementation of an efficient head tracking system is becoming more useful for a wide range of applications. In this paper, we make an attempt to solving realtime 3D head tracking problem on mobile devices by enhancing the fitness of the dynamics. In our method, the particles are generated by implicit motion estimation between two particles rather than the explicit motion estimation using corresponding point matching between consecutive two frames. This generation is applied iteratively using coarse-to fine strategy in order to handle a large motion using a small number of particle. This reduces the computational cost while preserving the performance. We evaluate the efficiency and effectiveness of the proposed algorithm by empirical experiments. Finally, we demonstrate our method on a recent mobile phone.