google maps not loading in my android application
<p>i have made an android application and in it , there is one scenario when the user clicks on an address and that address shows up on google maps. 
Now when i tested the application on the emulator, the google maps did load properly, but now that i am trying the same on my htc desire z, the maps is not loading.
Although the maps application which came built-in in my phone is loading google maps correctly.
what could be the problem? why is my application not able to load the map view?</p>

<p>thank you in advance.
EDIT: i have obtained a google map api key and have included it in the mapview that i am using.i have added overlays and etc. It is all showing fine on the emulator , but on my device it is not showing any maps. The overlays are visible.</p>
