While not exactly a competitor to the hot mobile payment startup Square, Google released last week a mobile payment option of its own for merchants and Android phone users. The company has developed the new Android Payment extension, which merchants can use to allow Android users to pay for items with Google Checkout, reports ReadWriteWeb.

Merchants first need to create a Google Checkout merchant account and then use the Gadget Wizard to embed the web store template on their website (they can also create a free Google Sites page just for this purpose). Then, after filling in their products in the Gadget’s spreadsheet, they need to install the Android Payment Extension for the Chrome web browser.

When a customer decides what to buy, the merchant creates a cart on their own computer and selects the green “Checkout with Android” button, at which point a QR code (a two-dimensional bar code) is generated for the purchase. The customer then simply scans the code with their Android phone and is directed to a checkout page where they can complete the purchase on their own.

It certainly doesn’t sound as dead-simple as Square’s checkout method — which entails customers swiping their credit card on a retailer’s iPhone or Android device with Square’s tiny card reader, and then going through a quick signing process. And since it requires an Android phone, the Android Payment Extension has little chance of taking on the more ubiquitous Square, which works on both Android devices and the iPhone. But it avoids the privacy concerns of customers handing their credit cards over to strangers, as well as other potential issues like the credit processing and risk prevention concerns currently delaying Square.

Eventually, Google may figure out a way to make the service accessible to the iPhone and other platforms. Most smartphones have the ability to read QR codes with the addition of apps, but the fact that there’s no standard way to do it on the iPhone and other platforms will forever be a hindrance to services that rely on the codes.

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