Android View port zoom

Hi,
I have porting game from iPhone to Android.It made of the TMX.
Now my TMX width is same as galaxy s3(1280x720) but all object looks small because high dip.
Can i zoom my view-port so that it will show me small part of the TMX at time and as object move it will show other part.
I have try to zoom all scene but it not working perfect,

please let me know you suggestion.

Thank you.