Google Maps on IPhone won't zoom

I have an iPhone app that loads the following URL:

http://maps.google.com?q=Apple Stores&开发者_开发知识库amp;ll=37.331689,-122.030731&z=3

As expected, the google maps app loads on the phone, but zooms to the entire US. It does not appear to be respecting the z= parameter, or at least, not allowing a zoom level that shows stores in the area.

z=3 zooms to the country level. z=1 zooms to the "world" level. Larger numbers increase the zoom. Try something like z=8 or 9

http://maps.google.com?q=Apple+Stores&ll=37.331689,-122.030731&z=9

Edit: On second thought, 10 or 11 might be more appropriate. I guess it depends on how close you want the zoom. The maximum is 19