Selina Tobaccowala co-founded Evite when she was in college, and, after selling it to IAC, took on senior roles at Ticketmaster. But then she met her mentor in Dave Goldberg, the CEO of Survey­Monkey, and she became that firm's president and CTO. His sudden death in May 2015 prompted her to get more active--and start a company to help others do the same. --As told to Yasmin Gagné

Dave Goldberg was one of the people who recruited me to SurveyMonkey. I immediately saw that he was someone I could learn a lot from. He came out to London to meet me, and I then interviewed at the firm's offices in Silicon Valley. When I landed back in the U.K., I had an email offer from the company. I also realized I was pregnant with my first child.

I told him I wanted more equity, I couldn't start for another three months, and that I was pregnant. Dave replied that he wanted to build a highly profitable business that also had a very strong family culture. When I saw his response, I immediately thought, "This is the guy I want to work for."

I learned so much from Dave. We were able to take the business from $20 million to $200 million in just about six years while still having a culture that was family-friendly. He left the office every day at 5:55 so he could have dinner and spend time with his kids--you could reach him between 6 and 8 only in an emergency. He was an amazing leader and an amazing father.

When he passed away, he was only 47 years old, and had two young children. I have two young children, and I want to be around for them for a long time.

I've never been fit. In high school, I was named captain of the basketball team, but that was because I'd built a stats program that helped them win. At SurveyMonkey, my only exercise was walking from my car to the train station. But I realized I wanted to build a business that would help people lead healthy lifestyles. Even a little physical activity can have a huge impact on your health. I started making small changes, like taking the stairs. I was thinking about how Netflix delivers movies, and wanted to give people access to fitness in a similar way. I left SurveyMonkey in April 2016. I took a week off to spend with my kids--they were on spring break--and then I went straight back to work. Gixo was incorporated that April 29.

My research told me the people who stick with fitness routines often go to classes. But classes can be unaffordable or intimidating, and a lot of people also live too far away or can't fit classes into their schedules. That's why my Evite co-founder Al Lieb and I created Gixo. Its app gives people on-demand and live fitness classes through their phones. Some of the classes are only 15 minutes, so it's good even for people who are really busy. One of our users is a busy working mom, like me, who couldn't find time to fit fitness into her routine until she found our app on iTunes. Now she can, and even works out on the sideline of her kids' sports games.

When someone close to you passes away, it can inspire you to make a change. I realized I needed to change my fitness level so I could be there for my kids. My dream is to change global activity rates and help people get healthier. But I also want to build a profitable business that has the family culture I saw at SurveyMonkey.