Visa and American Express are both reportedly trying to lure Apple's lucrative credit businesses away from Mastercard. But the battle over processing rights is just as much about accessing the technology company's digital wallet than it is about boosting transactions.

Visa has offered Apple $100 million to become the new network behind the Apple Card, as Apple prepares to replace Goldman Sachs as its i

The company wants to take over processing of payments for Apple's credit card, and has reportedly offered $100 million to replace Mastercard.