How Casumo scaled iOS user acquisition in the UK while keeping CPA in check

App category: iGaming | Campaign type: User Acquisition | Platform: iOS | Region: United Kingdom

• CPA held steady even as spend scaled more than 3x
• CPA per FTD stabilized roughly 15–20% below initial target 
• ROAS consistently outperformed benchmarks set by other non-incentivized channels

“Scaling usually comes with a tax. As you spend more, you often exhaust the cheapest inventory and CPAs start to creep up. The fact that Liftoff held our CPA almost flat while we increased spend by over 3x was a standout moment for us. It proved that the Cortex™-powered ML models were effectively finding new pockets of high-value users rather than just bidding higher for the same small pool.”

Miloš Tomić, Growth App Lead, Casumo

Casumo is an online casino built to turn gaming into an adventure, with a gamified environment full of rewards and progression that appeals to casual, entertainment-seeking players. The brand has a strong app presence in the UK, Sweden, Spain, and New Zealand, and is recognized as one of the leading challenger brands in iGaming.

The challenge: treating programmatic as a primary performance channel

Heading into 2025, Casumo’s UK acquisition strategy was heavily weighted toward social, search, and a handful of app advertising networks, with a focus on capturing high-intent users through traditional walled gardens. The team had experimented with programmatic before, but found it difficult to scale without sacrificing quality or running into transparency concerns.

Partnering with Liftoff represented a strategic shift. Programmatic would no longer be treated as a branding exercise. It would become one of the primary performance channels in one of Casumo’s most important markets.

The strategy: a CPA per FTD focus, with LTV as the long-term check

Casumo set a clear north star metric for the campaign: CPA per First Time Depositor (FTD). The team paired this with continuous monitoring of lifetime value (LTV) data to make sure the users acquired through Liftoff were not one-off installers, but high-value players who would return to the app over time.

Given the post-ATT landscape, the Casumo team approached iOS with caution. After an initial learning phase, however, the campaign ramped quickly. CPAs stabilized roughly 15–20% below the original target, and ROAS held consistently above the benchmarks Casumo saw on other non-incentivized channels.

The breakthrough: scale without the CPA tax

The defining moment came in Q3 2025. Casumo increased spend on the UK iOS campaign by more than 3x, expecting the typical scaling tax to push CPAs upward as cheaper inventory was exhausted.

Instead, CPA stayed almost flat.

For Casumo, this was the clearest signal that Cortex™, Liftoff’s AI-powered growth platform, was doing more than chasing the same small pool of users at higher prices. They were actively surfacing new pockets of high-value players, allowing the team to scale without trading away efficiency.

Brand safety and patience as performance levers

For an iGaming advertiser, brand safety is not a nice-to-have. It is a compliance requirement. Liftoff’s transparency around where ads run gave Casumo the visibility it needed to scale confidently in a regulated category.

Equally important was Casumo’s willingness to give the algorithm room to learn. Programmatic, the team noted, requires a different creative approach and more patience during the initial learning phase than other channels. By defining clear goals upfront and resisting the urge to over-optimize too early, Casumo set the conditions for sustained, efficient scale.

The impact: a foundation for what’s next

Since CPA held steady through significant scale and ROAS consistently above benchmark, Casumo’s UK iOS campaign has reset what programmatic can deliver for the brand.

The next chapter is about doing more with the same foundation. Casumo is expanding its re-engagement efforts with Liftoff, using ML-driven targeting to bring lapsed players back into the Casumo adventure. Acquiring a user, the team notes, is only half the battle.

As Liftoff continues to evolve its dashboard and platform capabilities, Casumo plans to keep building on a partnership that has turned programmatic from a cautious experiment into a core performance channel.