Pingo has recently slashed calling rates to India form 4.5 cents to 2.9 cents per minute.
This is for information purpose, if you have some remaining balance with it you can use it.
If you do not have possibility to use the internet connection to make VoIP calls, then Pingo could be a good choice.
Currently pingo is running following promotion from may
Pay 10$ and get 15$
Pay 20$ and get 30$
Click here for details
These offers reduced the calling rates by 33%
You can think, if its worth to buy phone credit from pingo.