GMAT vs GRE?

How to decide b/w GMAT and GRE? I am planning to self study and targeting the exam by end of July. Do not want to go abroad and have 3 years of work ex so ISB is my best bet here. Any suggestions on what should I go ahead with? I feel self starter groups and resources for GMAT are more than that for GRE (I am decent w english so planning for GRE but this seems to be a blocker) Is it really the case?