How CashBook Cut Their Meta CPA by 46% in 6 Weeks Using Linkrunner

Scaling paid acquisition without knowing which installs became users

CashBook's growth team opened the taps on paid acquisition, spinning up a full-funnel program across Google Ads and Meta Ads for Indian SMBs as well as the Middle East. By April 2026, they were running 75+ active campaigns across 45+ ad sets, spanning app-install objectives, conversion objectives, retargeting flights, and geography-specific creatives.

The problem was not getting installs. It was knowing which installs mattered. Ad networks reported install counts, but not what happened next. A campaign driving 5,000 installs at a great CPI meant nothing if those users never made it through onboarding. Worse, the team had no apples-to-apples way to compare Google vs. Meta on a metric that mapped to business value, because each platform self-reported performance differently.

Without an independent, campaign-level view of install to activation, the team would be optimizing for the wrong number. Budget decisions were being made on CPI alone, which meant cheap but low-quality campaigns kept getting rewarded while higher-intent campaigns were under-funded.

Independent campaign-level attribution tied to activation, not just installs

By wiring in Linkrunner as their mobile measurement partner, CashBook unlocked campaign-level visibility into the metric that mattered: cost per activated user.

• Activation-event attribution: every install was joined to CashBook's in-app activation event, completion of onboarding, so every campaign had a real CPA, not just a CPI.

• Cross-channel comparison on one activation event: Google and Meta campaigns could finally be compared on the same yardstick, instead of each channel's self-reported metrics.

• Install-quality breakdown by campaign and ad set: campaigns driving high-install, low-activation traffic were flagged quickly, so the team could reallocate budget toward audiences that actually converted.

• Reinstall and fraud detection built in: Linkrunner surfaced 1,000+ reinstalls, normally double-counted by ad networks, and flagged 240+ installs that failed verification across March-April, giving the team a cleaner spend picture.

CashBook cut Meta CPA by 46% and lifted blended activation rate by 14 points

Armed with Linkrunner's activation-level attribution, CashBook's growth team did in one month what most teams take a quarter to figure out: they stopped optimizing for installs and started optimizing for activations.

Monthly CPA breakdown: Meta Ads

In 30 days, Meta CPA dropped 46%, Meta installs scaled 2.5x, and activation rate climbed 7 percentage points, fueled by smarter budget allocation rather than just more spend.

Full-funnel picture: blended across Google and Meta

Despite scaling blended spend about 2.5x month over month, CashBook's blended CPA stayed roughly flat at about ₹29-31, because install quality improved dramatically. Activation rate jumped from 46.1% to 60.1%, a 14-point lift that meant almost every incremental rupee of spend was producing a real, activated user instead of a ghost install.

The headline discovery: Meta was cheaper than Google on activated users

On raw CPI, Google looked competitive. But once Linkrunner joined every install to the activation event, CashBook could see what was actually happening: Meta was delivering activated users about 28% cheaper than Google at ₹23.42 vs. ₹32.66 per activation. That insight, invisible without campaign-level, cross-channel activation-event attribution, now informs how CashBook allocates incremental budget as they continue to scale.

What drove the improvement

• Budget reallocation toward high-activation-rate campaigns: Linkrunner's activation data exposed which campaigns converted installs into users. The Conversions_Bookkeeping_0126 Meta campaign alone delivered 5,415 installs in March and 14,442 in April, the lion's share of Meta's activated-user volume.

• Retiring low-quality cheap-install campaigns: campaigns with attractive CPIs but poor activation rates were wound down, dragging blended install quality upward even as volume doubled.

• Geography-aware optimization: with separate campaigns for India (TenthEntry_Global) and the Middle East (TenthEntry_MiddleEast, Purchase_MiddleEast), CashBook could see activation rates per geo and concentrate spend in the markets where users were sticking.

• Cross-channel parity: with both Google and Meta measured against the same activation event, the team could judge channels on a common axis, with no more arguments about whose self-reporting to trust.

Activated user means a user completing CashBook's in-app onboarding flow after installing the app.