Google I/O 2015 has kicked off and as expected Android M has taken the lead. Apart from a host of reveals on the new OS, Google has also talked specifically about its mobile payment system, Android Pay.

Google Android Pay will work at over 700,000 US retailer locations. Google has partnered with several banks to make payments easier. But Android Pay goes beyond just shop payments using a smartphone in the real world. This can even apply vouchers, deals or loyalty cards automatically. In-app payment will be easier too.

Thanks to the open API the Android Pay system can be added to any app and is in over 1,000 already. But it gets better.

Fingerprint scanning has been standardised meaning that too can be used in any app. So if an app wanted to offer instant Android Pay using a fingerprint to verify that payment, it will be possible.

These systems will, of course, apply to Google's Play Store purchases too.

Google makes it clear that the user's card number is not shared with stores so the transactions should be completely secure.

Google has announced that Android Pay will begin rolling out later this year when Android M is launched. While it sounds like it will be US only initially, based on the partners announced, there is hope for Europe.

Visa Europe has released a statement saying it has partnered with Google and that 2015 will be the year of mobile payments. 

Jeremy Nicholds, executive director of Mobile at Visa Europe, commented: "Visa Europe is delighted at the prospect of working alongside Google to open up the Android Pay platform when it comes to European Visa cardholders."

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