Srinath Vaddepally’s lightbulb moment happened on a deserted Pittsburgh street at two in the morning. Vaddepally noticed a stranger walking behind him and felt threatened–and wished there was a way he could quickly and discreetly reach out for help. While nothing ended up happening to Vaddepally, he still felt shaken.

After hearing similar stories from friends and family, Vaddepally knew he had to do something. He was already working on a smartphone app where friends could share their locations. What if, with the touch of a button, you could share your location and ask for help at the same time?

He made it happen with AlertCall, a smartphone app that now makes it easy for people to send for help. Once installed, all someone has to do is “press the power button four times, and AlertCall shares your name and location with the friends you have added,” explains Vaddepally.

A screenshot of AlertCall, courtesy of AlertCall.

A screenshot of AlertCall, courtesy of AlertCall.

When you push the power button, friends receive this message: “I’m in an emergency, and I need your help. Don’t call me, call the police.”

The message also shares the GPS locations, user’s name and phone number. The beauty  of the app is in its simplicity, Vaddepally says. When a crime is in progress, it’s hard to reach for your phone, contact the police and let them know your exact location. AlertCall simplifies the process, giving friends and police the most valuable information quickly.

As Vaddepally and his team developed the app at the on-campus CMU incubator Project Olympus, they continued refining the experience using customer research. By partnering with a local women’s shelter, Vaddepally was encouraged to add other features to the safety app.

“I started talking to people who had been victims of domestic violence,” says Vaddepally, “and they suggested it would be helpful if the program also generated a noise to deter the crime.”

Now, when the user presses the power button four times, it not only sends an alert to friends but also starts a 30-second countdown. In the first 15 seconds, the app “records the situation to provide firsthand information to the respondents in a stealth mode so that the assaulters won’t know that victim has already alerted other parties,” says Vaddepally.

Selected contacts receive the recordings via email. After the 15 seconds of recording, the phone emits a loud alarm to deter the crime and alert anyone nearby.

For users who are in a dangerous situation but might not be able to speak, AlertCall also features a “Text to 911” option. When users press the “Text to City Police” button, the app sends a preconfigured message to the police including the name of the user and his or her GPS location.

AlertCall is available for free download in the iTunes or Google Apps Store in 79 countries. “It costs a lot to maintain the system,” admits Vaddepally, “but we offer the service for free because we feel it is an obligation to promote safety.”

In March, AlertCall completed a KivaZip loan application to help with maintenance costs of the app.

“My background is in safety,” says Vaddepally. “I’m more concerned about the security of the people, and I think this is my two cents contribution to society.”

In the future, Vaddepally hopes to integrate additional features, including contacts called “Guardian Angels.” This feature would help ensure that the contacts who are receiving your alerts are nearby and can more readily help.

Vaddepally explains his vision for the feature. “The signal goes to five people who you’ve recently had contact with. The probability of them being close by to you is much higher. You’d be getting the quickest help from the most relevant contacts.”

Vaddepally is encouraging students to download AlertCall. The team at AlertCall can share data collected from the app with the campuses to improve security and update the outdated technology of blue call boxes on campuses.

“This essentially is a blue call box in your hand,” says Vaddepally.

Visit AlertCall to learn more and download the app.

Emma Diehl, NEXTpittsburgh tech news writer also assists in creating content creation and social media for Carnegie Mellon Univeristy’s Center for Innovation and Entrepreneurship.