Creating a more accurate step counter.

I am currently trying to deisgn a Step Counter using Matlab Mobile and streaming the data recorded to Matlab Online. I have looked at using both the total number of number of zero crossing events and also the total number of peaks to record the number of steps taken. I am using the Acceleration Sensor.

I was wondering if there is a way to make the step counter more accurate or if using a different sensor would be better.