Key takeaways:
- Sustainable app growth requires strategies focused on achieving consistent, long-term results.
- Apps that scale successfully prioritize data-driven decisions, acquiring high-value users, testing and optimizing strategies, and prioritizing retention and re-engagement.
- Incorrect MMP setup and black box partners are the two major mistakes app developers make when trying to scale their apps.
Installs were once the end-all and be-all metric to gauge the success of an app.
But not anymore.
Today, every business aims to achieve sustainable growth by maintaining cost-efficient customer acquisition strategies and prioritizing high retention rates.
With user acquisition costs rising by 60% over the past years and only 5% of users remaining active after 30 days, experts agree that businesses can no longer rely on short-term tactics to grow.
In this interview, REPLUG Co-Founder and Head of Growth Luca Mastrorocco joins DesignRush to share key strategies for sustainable app growth, highlighting that businesses must focus on long-term gains.
Who Is Luca Mastrorocco?
Luca is a sales leader and an entrepreneur with over 10 years of experience in the digital and mobile advertising industry. Apart from co-owning REPLUG, he is also the co-founder of Mobile Marketing Italia, a comprehensive portal dedicated to enhancing knowledge and strategies in mobile marketing.
Building an app that drives sustainable growth is a key challenge many businesses face, especially with increased competition, rising acquisition costs, and evolving user expectations.
But how can an app truly grow sustainably?
Well, it’s definitely not by focusing on short-term tactics.
“Sustainable growth in mobile app marketing is about achieving consistent, long-term results by focusing on quality over quantity. It’s not just about acquiring users; it’s about building a foundation that ensures those users stay engaged, generate value, and contribute to the app’s evolution,” Luca explains.
He shares that at the core of sustainable growth are several key aspects:
- Deep understanding of the audience: Going beyond demographics and focusing on user behavior, motivations, and pain points allows you to tailor app acquisition and retention strategies to attract users who genuinely fit its value proposition.
- Operating efficiently: REPLUG helps clients identify inefficiencies in their growth strategies, such as misaligned channels, underperforming creatives, or overlooked retention opportunities. For example, leveraging innovative ad formats like OEM ads or combining ASO and Paid Activities to deliver a seamless user experience, helps ensure that every dollar spent drives meaningful results without inflating churn.
- Adaptability: The mobile industry evolves at lightning speed, and apps that thrive are those that are constantly testing, learning, and pivoting. REPLUG emphasizes an agile approach, using data-driven insights to continuously refine strategies. This process is then implemented across various app verticals.
- Aligning strategy for long-term impact: Aligning your strategy with user needs while ensuring that every effort contributes to a lasting impact. It’s not just about winning today but setting the foundation for success tomorrow.

How to Determine If an App’s Growth Strategy Is Truly Sustainable
I was curious to hear from Luca how REPLUG assesses whether an app’s growth strategy is built for sustainability when it starts working with a new client.
He answers that the first step is thoroughly evaluating the app’s existing growth strategy to determine if it’s truly sustainable.
The agency also follows a structured process that focuses on three critical pillars: alignment, efficiency, and adaptability:
- Alignment with the app’s value and audience
Check if the app’s growth goals align with its unique value proposition (UVP) and the needs of its target audience. A great app strategy starts with clear positioning and messaging that resonate with the right users. For instance, if the app is targeting high-LTV customers but is acquiring users through broad, low-intent channels, that’s a red flag. Brands must realign their growth efforts to attract users who will actually stick around. - Efficiency in acquisition and retention
Sustainable growth isn’t just about scaling installs — it’s about maximizing the lifetime value of each user. Dig into metrics like customer lifetime value (CLV), churn rates, and user acquisition costs (CAC). If there’s a mismatch between the cost of acquiring users and the value they bring, that’s another signal that changes are needed. - Adaptability to market changes
The mobile app ecosystem evolves rapidly, so a sustainable strategy must be flexible. Assess whether your app is testing new channels, iterating on creatives, or optimizing based on performance data. For example, apps heavily reliant on one channel or audience segment risk stagnation when trends shift. Businesses should diversify their growth efforts, including exploring underutilized opportunities like OEM ads.
“As part of our onboarding process, we always conduct a comprehensive app growth audit. This isn’t just about diagnosing gaps — it’s about creating an actionable roadmap to address them, across all areas relevant to app growth,” Luca adds.
Ultimately, he believes that assessing sustainability is about taking a brutally honest look at what’s working, what’s not, and what’s missing.
This no-BS approach has been a core part of REPLUG’s DNA since day one and is something its clients value deeply. This ensures that their growth strategy is not just built for today, but is also prepared to scale efficiently over the long term.
What Sets Successful Scaling Apps Apart from the Rest
Luca says that one characteristic he’s consistently noticed in apps that scale successfully and sustain growth is their commitment to data-driven decision-making and a deep understanding of their audience.
“These apps don’t just focus on acquiring users; they focus on acquiring the right users — those who align with the app’s value proposition and have a high potential for long-term engagement.”
Additionally, he highlights that successful apps are never static.
“They constantly test new channels, creatives, and strategies to find the most efficient ways to grow while keeping retention at the core of their efforts.”
Luca believes another standout trait is investments in retention and lifecycle marketing.
“Apps that sustain growth understand that the real value comes after the install. They prioritize onboarding, personalized messaging, and re-engagement campaigns to keep users active and engaged over time.”
Finally, he believes successful apps build strong cross-functional collaboration.
“Teams across product, marketing, and data work together seamlessly, ensuring that insights are shared and strategies are aligned. This level of integration allows them to act quickly when opportunities arise or when the market shifts.”
He concludes by saying that successful apps balance proactive testing and learning with reactive adjustments. This is key to ensuring long-term growth and a competitive advantage.

Luca shares a successful case study on Multipolls, an app that rewards users for completing surveys and tasks:
- The challenge: Multipolls relied on a single acquisition channel, limiting growth and insights.
- The solution: REPLUG implemented a multi-channel strategy, testing platforms like Google Ads, TikTok, Meta, DSPs, and OEM while optimizing creatives and value-based bidding.
- The results: Diversified acquisition, high-quality user growth, and a sustainable framework for long-term success through continuous collaboration and innovation.

The Biggest Mistakes App Developers Make When Scaling Too Fast
The world of mobile may move at blistering speeds, but Luca cautions developers not to get swept up in that pace. As the saying goes, “haste makes waste.”
“I’ve seen app developers make when trying to grow too fast are related to how they manage data and partnerships. Both can severely limit their ability to scale efficiently and sustainably.”
This isn’t the only pitfall developers should avoid as they look to grow their apps. Luca believes some of the other big mistakes developers make are:
#1: Not Having the App’s Mobile Measurement Partner (MMP) Set Up Correctly
He believes it is not uncommon to see apps spending heavily on acquisition campaigns while failing to track events like post-install behavior, retention, or LTV accurately.
“Without a properly configured MMP, developers are essentially flying blind. They’re spending money without accurate insights into what’s working and what’s not. This often results in assumptions about performance, over-investment in underperforming channels, and missed opportunities for optimization, Luca says.
REPLUG prioritizes data integrity, auditing MMP setups to track key touchpoints and align with growth goals for deeper user insights.
#2: Activating Partners That Operate as Black Boxes
He emphasizes that black-box partnerships prevent developers from learning what’s driving performance, which is a missed opportunity to refine and scale.
“Another big mistake is working with partners who provide little to no transparency at the placement level, often under the guise of offering fixed CPAs.
While the idea of predictable costs can be appealing, the lack of visibility into where and how ads are being delivered can lead to poor-quality traffic, wasted budgets, and an inability to optimize,” Luca notes.
REPLUG steers clients away from these setups. For instance, when exploring opportunities with OEM advertising, they work with partners that provide granular insights at the placement level.
This transparency ensures they’re making data-driven decisions, scaling the right channels, and maintaining ROI, while the client gets the full picture of what’s happening.
But how can you avoid these mistakes?
Luca advises businesses to:
- Set up your MMP correctly and validate your data: The foundation of any sustainable growth strategy is accurate, actionable data. Developers must ensure their MMP is set up properly, tracking all critical in-app events across all channels. They also need to validate this data regularly, ensuring it aligns with their internal analytics.
- Work with transparent partners: Transparency is non-negotiable when scaling growth. Avoid partners who operate as black boxes — those who offer fixed CPAs without disclosing insights into where and how your ads are being placed. Instead, prioritize partners who provide granular-level data, such as placement-level performance and user behavior insights. This allows you to identify what’s driving results and scale the right campaigns effectively.
- Take a test-and-learn approach: Growth isn’t a one-size-fits-all process. Developers should test different channels, creatives, and audience segments while continuously monitoring performance. The goal is to identify what works best and scale sustainably, rather than throwing money at channels that seem appealing but don’t deliver long-term value.
At the end of the day, Luca claims that sustainable growth requires patience, precision, and a commitment to data-driven decision-making:
"At REPLUG, we integrate these principles into every client engagement, ensuring their growth strategy is designed to adapt and thrive in a constantly changing mobile ecosystem,” Luca adds.
For businesses aiming to achieve sustainable app growth, they must prioritize data-driven decisions and long-term strategies to consistently see results.
They should also partner with app marketing agencies that provide granular insights and are transparent to drive strong ROI.
For businesses seeking a trusted partner in navigating the complexities of app scaling, REPLUG offers the expertise and dedication to help them achieve sustainable growth in the highly competitive app market.