LevelUp, the pay phone app from Cambridge, Mass.-based SCVNGR, announced it has hit a new milestone. The company said its 100,000 users now spend more than $1 million per month at local businesses in the eight cities it currently serves. The company said the each user uses the app on average 2-3 times per week to pay at nearly 1,400 merchants in Boston, New York City, Philadelphia, Atlanta, Seattle, San Francisco, San Diego and Chicago.

The self-styled "Chief Ninja" at LevelUp, Seth Priebatsch, said the company is "ridiculously excited" to have reached $1 million per month in transactions in only six months. He said that number is doubling every five to six days.

On top of announcing its new milestone, LevelUp also announced it has launched a new API that will let developers integrate its payment functionality into other solutions. It's a step that will help LevelUp expand retailer acceptance of LevelUp payments. The company said the API is currently in a beta release but that dozens of partners had already begun integrating LevelUp even before the API was released.

"While our API is initially focused on supporting POS integration for LevelUp, there are tons of other really cool things that developers can do with it," Priebatsch said, "and we definitely plan on implementing additional use-cases following the beta launch.”

Launched in 2011, LevelUp's mobile app is linked to a credit or debit card. The app generates unique QR codes that are scanned at the point of sale to make purchases. Additionally, users receive discounts and offers automatically applied to their purchases when using LevelUp to pay.

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