How a two-person team turned operational inefficiencies into successful ad monetization — in just 5 minutes.
Bustle Studio: From Side Project to Real Business
Could you introduce the Bustle Studio team?
CEO Sungeun Park: Bustle Studio registered as a business in 2019, so we've been working together as a team for about five years. Sumin handles Android and server development. I take care of iOS development, service planning, design, and overall business operations.
Was there a specific moment that made you commit to building Bustle as a real business?
Park: We registered the business early on, but both of us had full-time jobs, so it stayed a side project for a while. Last year, I left my full-time role to focus on the business in earnest.
A lot of people assume I quit because we already had solid revenue—but that wasn't the case at all. I'd been wanting to focus fully on Bustle for a long time, and at some point I just made up my mind.
Before that, I was still a junior with a lot to learn, so I hesitated. But one day, it hit me that I'd already learned everything I could at the company.
CTO Sumin Jin: I was working as a solo freelance developer at the time.
At first, Park still had her full-time job and Bustle was a side project, so I weighed it carefully. But there were so many real moments of growth I'd experienced through Bustle, and the teamwork with Park was great—so I jumped in.
How did you monetize the app in the early days?
Park: Even when it was still a side project, we were earning some revenue from in-app purchases and ad networks. But direct ads depend on advertisers choosing you, so it wasn't a stable stream—at first, I didn't really see direct ads as a major revenue source.
Our very first advertiser wasn't from outbound sales—they reached out to us first by email. We didn't know much about advertising at the time, so we sold the campaign at a very low rate. From then on, as new advertisers came in, we gradually figured out the right pricing.
How did you balance ads with user experience?
Park: Network ads always come with some friction. Direct ads vary depending on who the advertiser is. In the beginning, we made small compromises with users to reduce that friction. (laughs)
Compromises with users?
Park: We ran direct ads through popup placements, and the popup shows up at every login. Advertisers need a certain impression volume, so it was a tradeoff. The logic we built was: "Out of two times, please see it once."
On the first appearance, there's no "Don't show again today" button. On the second appearance, the button appears. That way we kept impressions up while keeping fatigue in check.
⇒ The popup ad: the "Don't show again today" button appears only on the second view.
And just how long did you run direct ads manually?
Park: A pretty long time. About three years, manually.
In 2021 we got our first inquiry from an outside advertiser. But our user metrics were still small, so we lacked confidence in our media value and had no real ad monetization experience—so we left a lot on the table.
The advertiser had a 1 million KRW budget to spend, but we priced clicks at about 70 KRW each. By the end of the campaign window, only about 200,000 KRW had been spent. The advertiser was willing to pay more, and we just couldn't capture it.
What was hardest about monetizing with ads?
Park: Honestly, every step after an advertiser inquiry was hard. With only two of us, we had our hands in everything—so we kept telling each other, "One way or another, we have to systemize and automate this."
What kinds of difficulties came up?
Park: Setting aside advertiser sales (that's a whole other story), the communication cost before and after a campaign was massive. Coordinating placement schedules, swapping creatives, etc. And advertisers wanted daily reports too.
Back then, we were filling out daily reports manually on a spreadsheet and sending them over. Since our system only surfaced numbers after 24 hours, we couldn't measure performance in real time. We eventually moved from CPC to a CPP model billed weekly.
Jin: Setting up an ad manually took about 30 minutes a day on average. Sometimes we had to update numbers over the weekend too. The total time wasn't huge, but the daily friction added up.
Park: We wanted to focus on one thing a day, but we kept getting pulled in different directions. The real cost was more than just the time spent on setup—the constant context-switching was the real loss.
What about technical challenges?
Jin: On the tech side, we didn't have a strong understanding of the ad business, and without a clear sense of the right specs, we ended up wasting some dev resources.
Park: Right. For example, an advertiser asked us to "scroll two image banners at once." Since meeting advertiser requests felt critical to landing the campaign, we'd pull resources from elsewhere to build the feature.
Jin: Yeah, product priorities were essentially flipping based on each advertiser's request. Short-term revenue mattered. And because we had limited ad-business knowledge and no clear standards, we felt like we had to accommodate everything.
What Made You Adopt AdControl, and What Was Your First Impression?
How did you find out about AdControl? What was your first impression?
Park: I came across it myself while researching ad admin tools.
I think I reached out asking whether there was an admin tool that could manage our direct ad process. The moment the open beta launched, we loved it and signed on right away.
Was the setup process difficult?
Jin: Not at all. The documentation was very well written, and the actual technical integration took about 10 minutes. If you've integrated SDKs like AdMob before, you'll find it really easy.
What Changed After Adopting AdControl
What did you love most about it?
Park: The intuitive UX. When I explained it to the advertiser's contact, they immediately got it: "Ah, this is like Meta's Ads Manager." They understood it on their own, so we didn't have to keep walking them through it—they just used it smoothly.
After the first campaign, the advertiser asked to buy ads again right away. The performance mattered, but I think AdControl itself was a big plus that led to the second campaign.
⇒ The screen where advertisers book campaigns themselves in AdControl.
Jin: Right. Advertisers were really happy with the screens they see. It's so easy that at each step, what they need to do next is clear.
We got a lot of requests from advertisers around rotating ad creatives, and we loved that the SDK supported it natively—no separate dev work needed. (Editor's note: App developers can also get daily reporting and per-creative performance metrics out of the box!)
Park: Running in-house campaigns is also a breeze. There were stretches where we didn't have an external advertiser running, but we had in-app purchase promotions or new feature launches to announce. Just by setting up an AdControl campaign, we could reach our users without spending any dev resources.
⇒ In-house campaigns Bustle Studio is running with AdControl.
If you didn't have AdControl, what would you be doing today?
Park: We'd have considered building our own ad center, on and off. Given the scope of that project, though, we probably wouldn't have actually started.
Jin: If we did build it ourselves, just an MVP would take up to six months—and that's before QA, before plugging it into Bustle, before building out the advertiser-facing admin. It'd take much longer once you factor all of that in.
And it'd be running in parallel with all the other features Bustle wants to ship. We can't only focus on the ad admin, so building it ourselves would have been the tail wagging the dog.
Park: Exactly. Even if we did build it, when an advertiser asked for a feature change, we couldn't respond as quickly as AdControl does, so it'd be harder to maintain. Going DIY just wouldn't have saved this much work.
Any memorable user feedback after running direct ads with AdControl?
Park: Thankfully, our users love the app and give us instant feedback. Recently, we partnered on a NEWNEEK promotion, and I got to chat with a user briefly about it.
They said: "NEWNEEK is already a service I have positive feelings about, and it feels somewhat relevant to Bustle, so even though it's an ad, it feels more like content. I'm fine with it." That was the first time I really felt that as long as it's not a totally context-less ad, users actually accept it to some degree.
Once operations got more efficient, we could partner with advertisers that were a better fit, and we had more bandwidth to pay attention to user reactions.
The Next Chapter for Bustle
What's on the horizon for Bustle Studio in the near future?
Park: We're working on a shared reading experience—reading together with others. Until now we've focused on individual reading life, but some users have shared that they'd love to share their reading log with friends, and we're listening.
Jin: We're also thinking about reading education features for schools and organizations. Some teachers are already using Bustle to guide students through reading. (Thank you!) We hope to help even more people discover the joy of reading.
For Bustle Studio, AdControl Is Like a New Teammate
Last question — would you recommend AdControl to other startup founders?
Park: Oh, I already have. The founder I recommended it to was also building solo. I told them that AdControl is easy to integrate, fairly priced, and simple to run. They immediately said they wanted to integrate it and start monetizing.
A lot of small startups never start ad monetization because they worry about building and maintaining a direct-ads system. AdControl removes all of those worries and lets you start running immediately. If you're running a niche service like ours, go meet the Adrop team!