Effectively, the new streamlined system makes any credit or debit card saved anywhere in your Google account available for purchases through any merchant or developer using the Google Payments. That means any card you've used to make a purchase on the Play store or saved in Chrome can now work with Android Pay. The API also extends to third party apps and mobile sites, so vendors can accept payment directly from your Google-linked cards, and you can be spared the headache of keying in your card number on a mobile page for the umpteenth time. (You will, of course, have to confirm any payments via fingerprint first.)Besides saving users a couple keystrokes at checkout, the simplified payments also makes it easier for Google Assistant to work its magic and order Panera Bread for lunch without actually asking you to take out your wallet. On the other hand, the ease of use should be taken with a grain of salt: as with all things Google, that level of deep access to your purchase and spending history will likely lead to some eerily specific marketing opportunities or advertisements down the line.
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