This research aimed to measure the coefficient of restitution (COR) for tennis and golf balls using smartphone sensors. The ball and smartphone were attached at the ends of a long plastic strip: one end was a pivot with the attached smartphone and another end was for the attached ball. The ball on the plastic strip was swung to bounce the ball. The experimental data, angular position and angular speed, were recorded using a smartphone's sensors (gyroscope sensor and device motion sensor) for analysis of the COR. The results of the COR obtained from both sensors agreed with the conventional method and references. We expect this experiment to be useful for physics lecturers to demonstrate the bouncing ball in the classroom or laboratory for determining the COR.