Josh Anton and his team are no strangers to building apps that go viral. Their first app was Drunk Mode: an app for going out that allows you to block contacts, retrace your steps, find your friends, and navigate home during an inebriated escapade.

After accumulating over 1.5 million users on Drunk Mode, Josh and his team went at it again creating an "exercise app for assholes." The premise is a little unusual: it's a fitness app that, instead of trying to motivate you positively, is actually on the meaner side -- but it's proving popular. Walk Against Humanity launched five months ago and already has over 165,000 users tracking their activity and getting motivation through mean jokes.

While both apps are different, the formula behind their success is largely similar. To create a viral app, you need to build something that stands out. Josh and his team do this by building apps with a unique, recognizable voice. For Walk Against Humanity, this meant Josh was "always trying to picture the person behind the words actually yelling at you."

What Made You Decide to Build an Exercise App?

Josh: It really started the day after the election. Without getting too political, it's safe to assume everyone at the office was pretty depressed the next day. I kept thinking about how we could employ our Drunk Mode technology in a new way, and I wanted to make an app to run away from Trump. I pitched the idea, "Trump Punch" to Jake, our CMO, and he was pretty wary of doing something so political. That being said, we all agreed that creating an exercise app with funny notifications was a pretty interesting idea.

Coming from Drunk Mode, we knew that creating an app with a slightly broader use case could yield a pretty interesting result with our technology. Our target audience has always been Millennials and families. Naturally, we consistently had the fitness realm in mind when thinking about potential use cases for our Drunk Mode backend work.

How Did Creativity Play a Role in Shaping the Idea?

Jake: I think there were two main things that started us in the right direction. First, I use my Fitbit religiously, and anybody who owns one knows that most other people who have a Fitbit are also pretty addicted. Second, the notifications provided by current fitness apps are just too peppy and cheery. I love Louis C.K.-style humor, and thus we decided to create the best exercise app for assholes.

Josh: Also, I think Drunk Mode played a massive role in shaping our direction and strategy. With our first app, we pretty much only talked to drunk people. It's not necessarily super niche, but it also isn't something that most people do every day.

Walk Against Humanity is essentially a fun version of the backend technology we used to make Drunk Mode. We started our research by talking to Fitbit owners and eventually downloading 200 of the top 500 fitness apps on the App Store. Fitness-tracking apps have been changing for years, but the way they try to motivate us has always remained the same. Our primary goal was really just to take a brand new angle on something that a lot of people incorporate into their daily lives.

How do You Make an App That Goes Viral?

Josh: It sounds obvious, but you really have to make sure you are actually building something people actually want. Walk Against Humanity is the only app to offer Fitbit integration besides their native app. Honing in on what your users want and need is vital to creating something they will want to use every day.

Once you do that, you need to make sure your app has personality. Throughout the development process, we focused on creating an app that had features people wanted and focused on presenting them in a completely unique way. When designing this app, we were always trying to picture the person behind the words actually yelling at you.

What's Next for You?

Josh: We've got a pretty massive Walk Against Humanity update slated for this summer that will give users the ability to challenge their friends. Gamifying is always great, and we hope to create a wave effect of friends pushing each other to work out more.

In regard to new apps, we're always trying to find specific audiences with wide use cases and daily behaviors. Our main goal is to keep it simple and continue to build awesome location apps with a unique personality.

Combine Utility with Delight for Growth

For those trying to build an app or any aspiring entrepreneur, the lessons here are clear. First and foremost, Josh & Jake's story reiterates one of the most important lessons in entrepreneurship: build something people want to use. All the marketing in the world won't save you if your product doesn't add value, so the key is finding something that offers a unique value proposition and solves a real problem.

The second takeaway is a little less common but just as important: build something with personality. While cruel jokes won't work for every business, the key point here is that your product - no matter what it is - should have a distinctive, recognizable voice. That's the way to really engage users, secure "mindshare," and build a product primed for growth.