How Planfit Reduced CAC by 40% Through UGC Creative Testing and Free Trial Optimization

About Planfit

Planfit is an AI-powered fitness app that provides personalized workout coaching. By analyzing inputs such as fitness goals, experience level, and gym environment, the app generates tailored workout routines. It guides users through exercise order, sets, and rest times, making it easy for beginners to get started without complex planning.

Planfit has grown into a fitness app with millions of users. It has seen particularly strong traction in the U.S. market, supported by a large and continuously growing dataset of workout records.

Overview

As of 2026, a growing share of Planfit’s downloads comes from outside its home market, reflecting its rapid growth. To scale further in the U.S., the team actively operated user acquisition campaigns. They tested a wide range of creative types, messaging, and audience combinations to identify which patterns led to actual subscriptions.

Using Airbridge, Planfit analyzed multiple in-app events and identified the strongest conversion signal. They found that free trial start had the highest correlation with paid conversion. Based on this insight, they shifted their strategy from install-based optimization to event-based optimization, resulting in a 40% reduction in CAC.

Planfit also built an environment where acquisition data, user behavior, and subscription data could be analyzed together. By integrating Airbridge with Amplitude and RevenueCat, the team was able to connect data across the full funnel. With Airbridge ShareLink, ad data was connected to internal dashboards, allowing the entire team to work from the same data and make faster decisions.

Challenge

Difficulty in Measuring What Drives Subscription Revenue

As Planfit scaled user acquisition in the U.S., the team ramped up creative and campaign testing to identify what actually drives subscriptions. They tested a wide range of creative formats, including creator-led UGC, in-house content, and routine-based content, while also experimenting with different combinations of targeting, messaging, and keywords.

However, for a subscription-based service, installs alone were not enough to evaluate performance. The user journey includes multiple steps such as onboarding, paywall entry, and free trial start. This made it difficult to determine which signals were directly connected to subscription revenue.

Planfit also evaluated performance based on LTV and CAC together. This required analyzing data across channels, creatives, and keywords, and identifying which events were most closely tied to revenue.

The Need for Unified Data Across the Funnel

As experimentation scaled, Planfit needed more precise visibility into marketing performance. It became critical to understand not just acquisition, but how users behaved after install and which sources actually drove subscription revenue.

The team used Airbridge for attribution, Amplitude for user behavior, and RevenueCat for subscription management. While each tool was effective on its own, the data was fragmented across systems.

As a result, it was difficult to view the full funnel from acquisition to subscription revenue in a single flow, making it harder to align on performance and slowing down decision-making.

Solution

Free Trial–Based Optimization Leading to 40% CAC Reduction

Planfit shifted from install-based optimization to focusing on the event most closely tied to subscription revenue. Over three months, the team tested multiple in-app events, including onboarding completion, paywall entry, and free trial start.

Airbridge enabled consistent tracking of these events across ad channels. By comparing performance across events, Planfit identified free trial start as the strongest indicator of paid conversion.

Based on this insight, the team optimized campaigns around cost per free trial, particularly on Meta. They accelerated creative testing and identified patterns that consistently drove subscription conversions.

With Airbridge reporting, Planfit analyzed performance across creatives, channels, and search keywords to identify which strategies were driving long-term subscription revenue. As a result, Planfit reduced CAC by 40%.

Full-Funnel Visibility with Airbridge, Amplitude, and RevenueCat

Airbridge supports integrations with tools like Amplitude and RevenueCat, enabling Planfit to analyze acquisition, user behavior, and subscription revenue in a single view. This made it possible to connect ad acquisition data with downstream user behavior and revenue, giving the team full visibility into the conversion funnel.

Planfit also used Airbridge ShareLink to sync ad data with internal dashboards. As a result, automatically updated acquisition data could be viewed alongside user behavior and subscription metrics in one place.

With this unified view, the team tracked key metrics on a daily, weekly, and monthly basis, allowing them to identify issues faster and respond more effectively.

Working from a single source of truth also improved team alignment. Instead of pulling data from multiple tools, the team could rely on one dashboard, reducing time spent on data validation and communication while accelerating decision-making.

Final Thoughts

Planfit scaled growth through continuous experimentation and data-driven decision-making. By identifying free trial start as the key conversion signal and optimizing around it, the team improved acquisition efficiency and reduced CAC by 40%.

By integrating Airbridge with Amplitude and RevenueCat, Planfit established a unified view of acquisition, user behavior, and subscription revenue, enabling faster and more consistent decision-making across the team.

Next, Planfit plans to expand into additional channels such as Reddit while continuing to scale creative experimentation. With this approach, the team will continue to drive growth.