Android does not provide the vertical accuracy.
Vertical accuracy usually is 2-3 times worse then horizontal accuracy.
A simple solution: use the androids accuracy for both horizontal and vertical.
advanced solution 1: find out what android uses as total accuracy (it could be a radial error of an error-sphere, including lat,long and altitude)
try to find out a conversion factor, e.g take accuracy and multiply *2,5
Another solution, look at iphone horizontal and vert accuracy, and compare to that of android. find out an average conversion factor from acc to vert acc.
Solution 3: think why you need vertical accuracy at all. why do you need that?
hints:examples from my iphone4: when iphone shows 30m hor, i have 57vert, 10hor: 15-20vert, 5 hor: 10vert