Reliance calling cards and Airtel Calling Cards have been fairly popular amongst people who make frequent calls from USA to India. Reliance calling cards were introduced a couple of years before airtel calling cards but the latter have quickly replaced the former primarily because of the cheap calling rates. Also many users of reliance calling cards have switched to airtel calling cards because they some how felt that reliance calling cards do not full fill what is promised in it’s various special schemes. Here is a quick comparison between reliance calling cards and airtel calling cards

Both reliance and Airtel provide special offers on calling cards from time to time. Currently airtel calling cards are offering IndiaOne plan which give 600 minutes of talk time for $6 (@ 1 cent / minute, 3 cent / minute from toll free number) with a validity of 45 days.
How to Call India