Though the majority of today’s payment transactions are digital – credit card swipes, online bill pay, tap-and-pay at point of sale, etc. – there are still a few places where cash has yet to die out. You still often need a handful of small bills to tip service professionals like valets, baristas, the great band at your local bar, and more. Taking these sorts of small payments digital is a challenge that Bravo aims to solve with its iOS and Android applications for simple, proximity-based payments.

The company, which presented on stage at TechCrunch Disrupt SF this afternoon after being selected as the “wildcard” winner through audience voting, was founded last year in Phoenix by husband and wife team, Dr. Hector Rodriguez and Maria Luna.

Dr. Rodriguez, whose background is in gastroenterology, originally came up with the idea for Bravo after experiencing the problem firsthand.

“Two years ago we were hiking in Southern Utah,” he explains. “And we had no cash to tip our hiking guide.” He realized that there were actually a number of situations where people are expected to tip with cash, but fewer people today carry bills in their wallet thanks to the growth of digital transactions.

Luna, meanwhile, has a marketing and administration background and MBA from the University of Texas in Austin. Together, the two of them have launched a number of startup businesses in the medical field, including a pathology lab, surgical center, medical offices, and an anesthesia company. But they have yet to work in the technology sector.

With Bravo, which was built with the help of a local development team, the idea is to offer service professionals and others with an easy way to accept payments from mobile consumers through a mobile application that doesn’t require users to exchange personal information like their phone number or email.

Instead, when a consumer launches the app, Bravo taps into the smartphone’s GPS to identify which Bravo pros are nearby and able to be tipped using the app. (The pros can turn on or off their visibility in their dashboard, allowing them to only be found when they’re ready to transact.)

After signing up for the app and scanning their credit or debit card as the payment source, you can launch the app at any time to see which service pros are nearby and able to be tipped. After tapping on the name you want, you can then tap on one of a few pre-filled payment amounts or you can enter your own. The following screen lets you optionally add a rating and comment, if desired.

Those who accept tips through Bravo provide their banking information in the app, which allows the payments they receive to go directly to their account. (Unlike Venmo, you don’t have to “cash out” later on.) The speed with which payments are deposited in a user’s account depends on the credit or debit card used and other conditions. But many payments arrive within a day, while others like American Express-based payments, take a few days, typically.

However, the actual payment processing is handled by Braintree on the backend. That means sensitive data isn’t stored in the app or on Bravo’s own servers, for security purposes.

In addition to finding service professionals to pay via proximity, Bravo also supports QR codes and search, in the case you want to send a payment to a company located further away.

The company generates revenue by taking a modest 2 percent transaction fee on all payments processed through its service.

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Since its launch in December of last year, Bravo has grown through word-of-mouth in the Phoenix area and today has thousands of monthly active users. It also now has 160 valet stations using Bravo in the area, each with around three employees, on average. In addition to valets, Bravo found that others including coffee shop baristas, bands, and even churches have begun to adopt the service – the latter, as an alternative to the traditional tithing process.

The company is also now working with a handful of charitable organizations, who are using Bravo to accept cashless donations, including the Alice Cooper Solid Rock Foundation; One Vision, One World; the Shadows Foundation; and the Phoenix Children’s Hospital.

Going forward, the bootstrapped team of three hopes to continue to expand Bravo, moving away from being solely focused on tipping to also allow for peer-to-peer payments and more.

Bravo is currently available for download on both iOS and Android devices.

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