In June 2016, Mai Medhat was attending the Global Entrepreneurship Summit in Palo Alto, California, when she got a call from a White House aide. Over coffee on Stanford University’s campus, the representative issued an invitation to Medhat: would she like to be on a panel with President Barack Obama and Facebook founder Mark Zuckerberg? The topic: what it’s like to run a startup in an emerging market.

“I was so shocked. It was a huge opportunity to not just represent my startup, but Egyptian startups in general,” says the 28-year-old Egyptian founder and CEO of Eventtus, an event organizer.

Dressed in a dotted print hijab, silky brown shirt and skinny jeans, Medhat held her own on a panel that included entrepreneurs from Rwanda and Peru.

“What are some of your biggest hurdles to success as an entrepreneur?” asked Obama.

“I think I made every single mistake you read about in entrepreneur books,” Medhat answered, listing challenges common to anyone starting a business, including funding, red tape and building a team. “The only thing that keeps us growing is believing we can add value to people’s lives,” she said to a round of applause.

The publicity is money in the bank for Medhat’s four-year-old startup. She expects Eventtus’ revenues to increase five-fold from 2015 to $500,000 this year. It has raised $425,000 from Middle East Venture Partners, Vodafone Ventures, Cairo Angels and Raed Ventures, landing Eventtus on FORBES MIDDLE EAST’s inaugural list of 20 Most Promising Startups at number 12. Medhat and her co-founder Nihal Fares, 28, who is Chief Product Officer, own an undisclosed stake in the startup.

Their customers are some of the biggest names in tech conferences, including ArabNet, RiseUp Entrepreneurship Summit and Dubai Expo 2020.

When Omar Christidis, the CEO of ArabNet was looking in 2014 for a digital platform to organize his four annual conferences, he looked at several companies, including Cvent, Double Dutch and Crowd Compass and custom app developers, such as Mobibus, Trifork and Eventmobi. Eventtus came out on top.

Attendees who downloaded the app were able to message other participants, customize their agenda in Arabic or English, and receive notifications from ArabNet alerting them to activities in the exhibit hall or upcoming speakers. The organizers were also able to conduct polls.

Post-conference, Eventtus provided a report, analyzing how many people exchanged in-app messages, what sessions they attended and what exhibits were the most popular.

ArabNet has just renewed its contract with Eventtus for conferences in Dubai, Beirut, Riyadh and Kuwait, “Every time we’re doing an event we are learning and honing our strategy,” says Christidis. “We’re seeing how people are using [the Eventtus app] and changing how we use the app in real time.”

Eventtus’ basic app, with conference information and social media integration, is free. Otherwise, the service ranges from $599 to $1,399 or more for customization, and includes notifications, polling during events, and analytics.

When Medhat and Fares founded Eventtus in 2012, it was an inauspicious time to start anything in Egypt. The country was still coming to grips with Mohamed Morsi, its new president and power outages, violence and looting were common.

None of that deterred Medhat. “After the revolution, we had huge pride and hope,” she says. “We felt that we can actually achieve anything if Egyptians managed to get Mubarak to step down. Anything else looked achievable.”

Her love of technology started early. Medhat’s first computer was a gift from her maternal grandfather when she was in fifth grade. He ran a small newspaper printing shop in Cairo, the family’s hometown. “The idea that he started something and worked for himself was very compelling to me,” she says.

She loved browsing the Internet, because it connected people around the world and was a font of information. By high school, she was moderating Yahoo chatrooms and coding with her friends celebrity fansites.

In 2009, Medhat graduated with a bachelor’s in electrical engineering from Ain Shams University, where she met Fares, a fellow code enthusiast.

While at Ain Shams, they designed a navigation app to provide real-time information on traffic conditions, and entered Microsoft’s Imagine Cup, an international competition that challenges students to solve problems using technology. They won first place in Egypt, but didn’t make it in the finals.

“Me and Nihal felt like we failed, because we failed to get it to market,” says Medhat. “I realized then there are a lot of experiences I needed to learn outside of university.”

She and Fares diligently tried to learn what makes Silicon Valley startups successful. “I wanted to know how they started, why they launched this feature and not this feature and looking at all these things helped us understand more about startups in general,” says Medhat.

While she and Fares worked 9 to 5 jobs as software developers—Fares for French telecom Orange and Medhat for a firm focusing on customer relationship management tools, they attended networking events in Cairo for developers and entrepreneurs.

In 2011, they went to TEDX Cairo and Startup Weekend Cairo to connect with other techies. They left disappointed. “The nature of Twitter was that you’d go to events and you know who people are based on their avatar on Twitter, but you can’t recognize their faces in the real world,” says Medhat.

Still, even with sporadic gunfire in the streets, there were around 750 people at Startup Weekend. With so much pinging back and forth via direct messaging on Twitter and some attendees not even on social media, Medhat saw an opportunity.

“You see organizers running around telling people a coffee break is over and to get in the conference room,” she says. “Or if the agenda is shifted by 10 minutes things can get disorganized quickly. What if you could edit the agenda online in real time? Everyone here has a smartphone, and if organizers can send push notifications then that problem is solved.”

Within a week of coming up with the idea for an event management app, Medhat and Fares quit their jobs in the spring of 2011.

They worked eight hours a day in coffee shops for the free WiFi, and spent late nights at home to code the app. They built tools for ticketing and registration, agenda and messaging templates, among other things. To save money, they signed up for a free 12-month trial of Amazon cloud services.

In late 2011, Medhat pitched a very early version of the app at ArabNet’s first conference in Cairo. Mohammed AlAyouti, a Vodafone executive who was in the process of setting up a venture capital fund for the telecom giant, was impressed. He  agreed to serve as mentor, providing feedback on features.

Medhat and Fares focused on free events for fewer than 100 people. They relied on friends in the tech industry to try out Eventtus. “It was very hard to get the first paying customer,” recalls Medhat—citing the biggest hurdle any startup faces.

Several events were cancelled because of the unstable political situation, but that proved fortuitous. Event organizers liked the fact that Eventtus could easily notify attendees of a cancellation or a change in program.

After putting around $30,000 of their own money into Eventtus, Medhat and Fares landed their first paying customer in 2013. RiseUp Entrepreneurship Summit was planning its first conference in Cairo, and expected around 2,500 attendees. “[Eventtus] seemed almost too obvious,” says Col O’Donnell, RiseUp Summit’s co-founder. “We’re very grassroots; registration, ticketing, furniture, we try to rely on startups.”

With their first customer and $40,000 from Cairo Angels, Medhat and Fares reached out to Vodafone’s AlAyouti again. He invested $135,000. “[Eventtus] knew what they wanted and always had a clear vision,” says AlAyouti. (As part of a strategic shift, Vodafone shut down its venture arm earlier this year, and is looking to sell its stake in Eventtus).

Another investor, Omar Al Majdouie, was also impressed. The head of a family manufacturing company in Saudi Arabia, Al Majdouie had recently set up Raed Ventures to invest in early stage startups.

He had used the Eventtus app to register for TedX Dubai a year ago, and liked the fact that it facilitated networking. He assumed the startup was American or European. “It was surprising to me that it was an Egyptian startup,” he says. “I found [Medhat] very competent and capable, with a very good vision for the company.”

Raed Ventures invested $150,000 this year as part of a $250,000 funding round with Middle East Venture Partners. Eventtus is using the money to further develop the app, and hire its first two employees in Dubai, where it has contracts with the STEP Conference and ArabNet. The team in Cairo, now 20 strong, is building an interactive map, which will allow attendees to search for exhibitors.

In November, Eventtus will be hosting its biggest conference yet for DMG Events, a British company. Some 80,000 attendees and 3,000 exhibitors will be able to log into the Eventtus app to guide them through the largest construction conference in the Middle East at the World Trade Centre in Dubai.

Medhat now spends most of her time in Dubai. But last week, she was home and people recognized her on the streets of Cairo. Medhat says she’s “that girl in the hijab onstage with Obama, talking about startups.” Her panel has racked up nearly a quarter of a million views on YouTube. “They see me, and know that just a regular girl like them can build something.”