Toss, the “super app” from South Korea, has won widespread adoption in its home country with 24 million monthly active users (MAUs) as of July 2025. The Toss app—known as a super app because it combines multiple services into one platform—appeals largely to younger, mobile-savvy users who want to manage personal finance tasks in one place.
Since most people originally used the app just a few times a year, Toss began introducing as many as 40 new services annually to boost engagement, such as Toss Walk, a step counter to help monitor physical fitness. To generate new revenue while maintaining the user experience, Toss partnered with Google, choosing AdMob because of its technical stability, focus on ad quality, and dedicated support team.
Monetizing engagement while strengthening brand trust
As Toss experimented with ads, the team wanted to engage users, but also preserve the brand’s positive image. The ideal experience would be ads that held user attention but weren’t intrusive.
However, initial results showed lower engagement than expected. Users closed the Toss app as soon as ads appeared, a sign that the ads did not provide enough value. The ads needed to provide a more engaging experience that was true to the brand.
To improve the ad experience, Toss decided to monetize app engagement using programmatic ads to make the Toss Walk feature sustainable, while maintaining customer trust. With programmatic ads, Toss could deliver immersive ad experiences that would better engage app users across any device or platform.
An ad solution that scales
With brand protection at the top of its must-have list, Toss needed a partner to support scaling of ads, but they also wanted to prioritize the UX and ad quality in service of the brand. To support its objectives, the company chose Google AdMob—in large part because of the solution’s technical ability and dedicated support.
AdMob stood out to the Toss team for its ability to provide real-time ad review and blocking, actionable analytics, and innovative in-app ad formats. The ability to review ads, and choose whether to continue showing them, helped Toss preserve the brand experience while monetizing.
Toss also valued Google’s criteria for user experience (UX) and ad quality, which aligned with its commitment to maintaining brand safety. With over 200 million ad impressions being served daily on the Toss Walk app alone, technical stability was crucial. Google’s infrastructure assured Toss that AdMob could consistently serve its ads. In addition, the Toss team appreciated the prompt and robust support from Google, ensuring quick resolution of technical questions and operational problems.
Paying attention to UX and brand integrity
Toss started small, using AdMob to introduce ads and doing A/B testing with small user groups at first, and gradually expanding scope and scale. While ad efficiency was important, Toss carefully monitored traffic to confirm that user numbers and activity were not adversely affected. Toss also designed and tested various strategies and placements, such as in-app ads whose UX is integrated with app functions.
Ads like playables prompted positive feedback from some users. Such feedback was very helpful for Toss, and has become a source of ideas for future initiatives.
Active users grow along with year-over-year revenue
Toss saw an 891% year-over-year jump in ad revenue from April 2024 to April 20251. Just as important, the ad rollouts didn’t slow down user growth. In addition, the new ad inventories showed no negative impact on retention and engagement.
In this same time period, Toss saw a 17% year-on-year increase in next-day retention for the app’s Toss Walk feature, driven by consecutive days of walking activity that allows users to earn points when they achieve specific step milestones within the pedometer feature.
Powering these results is AdMob, achieving a fill rate of over 95%, and delivering a 34% increase in CPM compared with the previous Toss mediation platform.
The success of the AdMob partnership is inspiring fresh ideas for more Toss initiatives that drive value while preserving the user experience. Toss plans to deploy AdMob for premium placements that used to be filled by direct sales, and for the app’s upcoming expansion outside of South Korea.
1Actual results may vary.
