Will an AT&T iPad purchased from Best Buy US work in india?
There are 2 options.

First you will have to have AT&amp;T unlock your device.

Then you will need to find a provider in India that will support your device.

Alternately (but costly) is to open an International roaming account with AT&amp;T.

Check here:

http://www.wireless.att.com/learn/international/roaming/travel-guide.jsp?

Technically speaking, you device will work in India.

Check here

http://www.wireless.att.com/travelguide/coverage/roaming/step3.jsp?CIDL=356&amp;CTN=&amp;MNC=SHOP&amp;DID1=468&amp;DID2=&amp;devicenum=1&amp;STEP=3