Patrick Moorhead, an analyst at Moor Insights & Strategy, called the new Square reader a "big deal" for small businesses.
Overall, he said Apple's expansion of Apple Pay shows the company is "well on track" to hit the goal of providing Apple Pay at half the 100 largest retailers in the U.S. by the end of the year.
Google recently announced that Android Pay will support rewards cards once it launches in the fall.
In a related announcement, Apple said it was updating its maps capability with iOS 9. One new maps feature will include the ability to see if a retail location supports Apple Pay with a small icon that appears in the retailer's thumbnail description inside the maps app.
Privacy and security have already been features of Apple Pay and in other Apple apps, but were mentioned again at WWDC with regard to the coming iOS 9. The upgrade will provide "intelligence without compromising privacy," said Craig Federighi, senior vice president of software engineering.
He declared that data on an Apple app "stays on your device under your control...We honestly just don't want to know [it]."
The comment could be considered an obvious swipe at Google, which is expected to mine user data for advertising and related purposes.
In Apple's case, user data is not shared with third parties or linked to Apple services from searches or other functions, Federighi added. "Why would you do that?" he asked.
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