Each previous form of mobile payment has run into one problem or another. Google Wallet, for example, was hamstrung by limitations on the types of phones and cellular networks with which it was compatible, leaving Google to focus its mobile commerce efforts elsewhere. Softcard, the product backed by major wireless carriers, has seen little enthusiasm for its mobile wallet for similar reasons.

As a result, cash and credit cards remain the norm in physical stores. So consumers have been unconvinced that paying with a phone at the register is any faster or safer than doing so with a credit card.

And online, only 11 percent of e-commerce spending happened on mobile devices in the second quarter, according to data from comScore, an Internet market research firm. The rest is made on desktop computers, largely because it is easier to enter payment information on a desktop than a smartphone.

“Apple Pay is good for everyone in the payments ecosystem because ultimately, it increases the amount of transactions that are happening on mobile,” Mr. Collison said.

With Apple Pay, which is expected to be available within a month, people can pay online or in person with their phone, using an iPhone’s fingerprint sensor to check out, an experience that Apple says will be faster and safer than offerings from its predecessors. Many major restaurant and retail chains, including McDonald’s, Whole Foods and Macy’s, have signed up to accept payments this way.

Part of the scramble among companies comes from Apple’s reputation for upending other industries. The iPod, for instance, revolutionized how consumers buy digital music. The iPhone has changed the way people use their cellphones in their daily life.

Companies large and small think Apple’s payments service could potentially have the same effect.

“Apple in particular has a reputation of harnessing and mobilizing an ecosystem,” said Denée Carrington, an analyst at Forrester Research.