If Apple does use this approach, Hall expects the company would collect a small transaction fee, maybe around a penny per use. He also does not expect that Apple will include debit cards initially, due to more stringent regulation of such cards, and due to the fact that debit cards are directly tied to bank account funds. In this scenario, even if all 444 million iPhone users were to utilize "iWallet" for 100 percent of their credit card transactions, Hall estimates that the penny-per-use sum would lift the company's earnings by just 0.5 percent, or 4 cents. In that respect, Apple's anticipated mobile payment system is not expected by Hall to have a significant effect on the company's bottom line. In a note to investors on Friday, a copy of which was provided to AppleInsider, he indicated he believes Apple's rumored payment system is more about locking users in to the iPhone and larger iOS ecosystem, making it harder to leave for competing platforms like Google's Android. The so-called "proxy" approach wouldn't be Apple's only option for a mobile payment system. Hall noted that Apple could also become a merchant of record, which would require it directly interact with merchants — an approach that seems to the analyst like it would be too complex for Apple to want to attempt.