When Twitter cofounder and Medium founder Evan “Ev” Williams was planning his 50th birthday party, he didn’t know who to invite. Having spent more of his life building and scaling tech companies, he found himself feeling disconnected from friends. That’s why he started Mozi last year with Molly DeWolf Swenson, a marketer and producer. Swenson, who serves as CEO of the company, says that the app—which lets users check in to certain locations where other contacts can join them and vice-versa—is intended to facilitate spontaneous, in-person interactions.  Launched in December 2024, Mozi raised $6 million in seed funding from Williams’ Obvious Ventures—which he cofounded with Vishal Vasishth and James Joaquin—and is live in 135 countries.  During South by Southwest, Swenson and Williams joined Most Innovative Companies host Yasmin Gagne to discuss what inspired the app, how it works, and how they plan to make money off of it. This interview has been edited and condensed. How does Mozi work? MDS: You set up a basic profile. The only information we require is what city is your home base, a photo, your phone number, and your name. Then you sync your contacts so that we know which of them are on Mozi.  Then you can decide whether you want them to be able to see your plans or not. Then as you go, you input your travel plans or your local plans. The idea is that you open up Mozi and you see where your friends are and the things that they’re doing that you could join them for, whether that’s coworking at a coffee shop, or going to a show that night. Those are the kinds of things we’re trying to drop people into. It’s not something where you’re spending a bunch of time on your phone. You’re actually getting together in person. Molly, what attracted you to the business? MDS: I had a spreadsheet of 450 people that I started at my first company, Riot, which was a media company. We’d be traveling back and forth to New York a lot and I’d be like, ‘I’ve got to remember to reach out to these people when I’m in New York.’ So it just started with ‘Who are the important people I need to remember to reach out to that live in New York?’. And then that expanded to ‘Who’s in San Francisco?’ and ‘Who’s in these other cities?’ Then that list ended up expanding to potential clients, people with audiences, people who are single so I could set them up. It wasn’t very accurate for very long because it takes a lot of effort to keep something like that up to date. So when Evan and I came together to talk about Mozi for the first time, I described the spreadsheet to him. Do you worry about the app promoting behavior like stalking? MDS: It’s encrypted as fuck in terms of personal information. We’ve been really, I’d say conservative on making sure that privacy is protected for you and your contacts.  EW: We don’t just broadcast your location to everyone. We only tell people the plans you share with a subset of your contacts. Nothing in Mozi is public. Can’t you just text your friends to make plans? EW: But through Mozi you could share plans with people who you want to know better as well. How are you going to make money through the app? MDW: Premium features. There’s dating apps now that people will pay for, there’s health tracker apps that people pay for. There’s tons and tons of utilities on our phones that people are willing to pay some amount for. you We have a thesis that people would be willing to pay for an app that is purpose-built for maintaining and strengthening their friendships and relationships. People write to us saying, “I’d be willing to pay for a product like this, just don’t bring ads into it.” A lot of our users initially—Mozers, as we call them—are in an older demographic. They’re in their 20s, 30s, 40s, 50s. They’re less price-sensitive than some of the [users of] social platforms that are targeting younger users. EW: Mozi is really in the category of utilities. The types of apps Molly was mentioning are utilities; they can charge a subscription because people don’t spend all day on them. You kind of need people to spend all day on the app if you’re going to make an ad model work. We’re not focusing on monetization right now. We need to grow the network. But it seems very likely to us that this can provide such value in life as a utility. What would a premium feature look like? MDS: We prototyped a map view with a slider into the future. You could, at the city level, see where your friends are, then you slide into the future with your finger and all those little bubbles move to different cities where they will be. That could be one. I’ve also talked about this feature of being able to sort my contacts by who is single so I can set them up. EW: Another cool feature idea is an intro feature where if you see two people who don’t know each other who are going to be in the same place, you can introduce them. Normally that would take a good six text messages, but in the app you could do it like boom, boom, if they both opt in. MDS: We actually had a cool Mozi moment yesterday. Two people connected at the Mozi event and they realized they had the same birthday– they just happened to see each other’s profiles. We should have just popped that information up when they connected on the app. There’s things like that where you connect and it’s like…here’s your common ground. How do you figure out you have the same birthday that fast? Evan, you cofounded X (formerly Twitter). What is your relationship like to social media now?  EW: I don’t spend much time on it at all. I just think for mental health and for ROI on time invested, I like to do other things. Twitter is still an amazing source of tech information if you want to know what’s happening. If you want to recruit people, LinkedIn is social media. But now I’m just enjoying my time reading books and hanging out with friends. Have you made any friends through Mozi? MDS: We found out a friend was in Kyoto and went out to drinks with her and her brother because of Mozi. I heard from someone yesterday who was like, “I ran into someone because of Mozi in Dubai. We hadn’t seen each other in four years.” It feels like we’re delivering on something important. We want to increase the surface area of that social serendipity.