The Quality of Experience (QoE) provided by autostereoscopic 3D displays strongly depends on the user position. For an optimal image quality, the observer should be located at one of the relevant positions, called sweet spots, where artifacts reducing the QoE, such as crosstalk, are minimum. In this paper, we propose and evaluate a complete active crosstalk reduction system running on an HTC EVO 3D smartphone. To determine the crosstalk level at each position, a full display characterization was performed. Based on the user position and crosstalk profile, the system first helps the user to find the sweet spot using visual feedback. If the user moves away from the sweet spot, then the active crosstalk compensation is performed and reverse stereo phenomenon is corrected. The user preference between standard 2D and 3D modes, and the proposed system was evaluated through a subjective quality assessment. Results show that in terms of depth perception, the proposed system clearly outperforms the 3D and 2D modes. In terms of image quality, 2D mode was found to be best, but the proposed system outperforms 3D mode.