An electronic device is provided. The electronic device includes a motion sensor and a processor. The motion sensor is configured to perform a sampling at a sampling rate. In each sampling, the motion sensor generates a sample by sampling an angular velocity or an acceleration of the electronic device. The motion sensor is further configured to store each sample in a buffer of the motion sensor. The processor is coupled to the motion sensor and is configured to perform a polling at a polling rate. In each polling, the processor fetches a plurality of the samples from the buffer. The processor is further configured to perform a numerical integration based on the fetched samples.