Cantaloupe Systems is gearing up to launch Google Wallet in vending machines across Chicago, San Francisco, New York and D.C., according to All Things Digital.

So far the Bay Area start-up has installed NFC technology into 6,000 of the 80,000 vending machines in its network. Once complete, customers will be able to pay for drinks and snacks with a simple tap of their phone.

In addition to greater convenience, the new service could introduce coupons and rewards offers into the vending machine industry. Mobile apps could even allow customers to submit requests for items or complaints about machine malfunctions directly to operators.

The new technology could help revive the sagging vending machine industry, which has seen sales fall 18 percent to $19.25 billion from 2008 to 2010, according to ATD.

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