Until now, Apple Pay has been exclusively app based. You could pay for stuff in person with the Apple Pay app or within specific companies' apps like BevMo, Best Buy or Crate and Barrel. But it was always within that specific app itself.

Now, however, if you're on, say, the Crate and Barrel mobile website, you'll be able to pay the same way you would through the branded mobile app. Plus, you won't have to manually enter your credit card info on the website; it's all taken care of through the Apple Pay system. The new functionality should begin rolling out to nine countries in the near future.

This new feature puts Apple Pay squarely in competition with PayPal as they're basically now offering the same service. However, Apple has a decided advantage. It can leverage its massive -- and tightly controlled -- ecosystem of mobile devices and wearables to make the buying experience as seamless as possible to its users. Pressing the fingerprint pad or tapping a watchface are both infinitely easier than conventional log-in systems. It's going to be interesting seeing how PayPal responds to the new competition.

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