I think you got them confused.
Fring allows communication over Skype, Google Talk, MSN etc.. Calls to Skype is free, and if you make calls to ANYWHERE else, you get charged the Skype rate, to your Skype account.
Messages sent to GT, MSN etc is free as per usual from a text messenger.
Truphone on the other hand, integrates with the Nokia
N95 software, in such a way that it is almost not a third party application.
It can make free phone calls to US Landlines and Mobiles, and to 40 other countries worldwide. You also buy credit for Truphone if you want to text or calling a location other than the FREE areas. In my experience Truphone has been cheaper and an overall better experience on the
N95 than fring.