How to Choose a CPA Marketing Agency: Key Factors to Consider

According to a Wave Tech Global report, the most dynamic growth in CPA marketing will occur in the fintech, health, and iGaming niches in 2025. Maximum effectiveness is achieved by partnering with specialized mobile marketing agencies that possess the expertise and access to the right channels. Before diving into how to choose the right outsourcing partner, let’s explore what the CPA and CPI models stand for.

What are the CPA and CPI Models?

CPA (Cost-per-Action) is a model where the advertiser pays only for a specific target action. For example, a product purchase, app registration, credit card application, service subscription, etc.

CPA = Total advertising spend / Number of target actions

For example, if you spent $1,000 on advertising and received 200 target actions. The CPA would be $5 per action.

CPI (Cost-per-Install) is a model where the advertiser pays only for each mobile app installation.

CPI = Total advertising spend / Number of installs

For instance, if you invested $500 in a campaign and received 250 installs. The CPI would be $2 per install.

These models are especially relevant for promoting mobile apps and digital products, where it’s crucial to pay for results, not just reach.

The Pitfalls of Working with a Fixed Budget

When promoting a mobile app on a fixed-cost basis, businesses often face several obstacles that hinder effective scaling:

• Wasted ad budget. Your ads may receive plenty of visibility. But the desired action, such as a purchase in an e-commerce app or a credit/debit card application in banking, might not be completed.
• No guarantee of deep in-app events or metrics. While you can calculate CPA, LTV, ROAS, and CAC, influencing these metrics under a fixed-budget model can be challenging. Ultimately, the risk of product payback still falls on you. You’re essentially just paying the agency for ‘hands on deck.’
• Lack of qualified leads. Even with a fully spent budget and high volumes of impressions, clicks, installs, or other top-funnel events, there’s no guarantee you’re reaching the right audience. As a result, conversions remain low and outcomes uncertain.

How Can a CPA Marketing Agency Help You Avoid Them?

If you want to drive real performance from your marketing efforts, it’s worth outsourcing to a CPA-based model. There are key benefits of partnering with a CPA agency:

• Preserve ad budget. Specialized performance-based agencies are laser-focused on your unit economics. You only pay for predefined, high-value actions, not just impressions or clicks. Unlike a fixed-budget model, there’s no guarantee that all KPIs will be met.
• Broader access to mobile traffic sources. Mostly in-house or fixed-budget teams often rely on the usual suspects: Google Ads, Facebook Ads, and TikTok Ads. Specialized mobile agencies, however, have access to high-engagement in-app networks, OEM traffic, and niche sources that better align with your audience and campaign goals.
• Entry cost savings for in-app platforms. Most in-app platforms require a minimum deposit (often $5,000 or more) just to launch a campaign. If your in-house team lacks deep expertise in a specific in-app or OEM channel, there’s no guarantee that the budget will deliver results. A CPA marketing agency already has access to all relevant ad accounts. So when you partner with them, you avoid those upfront fees.
• Quality control. CPA agencies leverage analytics tools like AppsFlyer, Adjust, and AppMetrica, along with anti-fraud protection, to eliminate low-quality traffic sources.

Key Factors to Consider When Choosing a CPA Marketing Agency

Remember that choosing the right CPA agency is a critical step that directly impacts the success of your campaign. Mistakes can be too costly. The wrong agency choice can lead to a wasted budget, irrelevant leads, or even large volumes of fraudulent traffic disguised as result. It’s not enough to go with the lowest price or a generalist agency. Instead, look for a niche partner with proven expertise in your vertical—one that can achieve your goals efficiently and without any waste.

Key factors to consider when choosing a CPA agency include:

1. Vertical specialization. Rely on a CPA marketing agency that works within your niche. For example, if an agency has only collaborated with VPNs or fitness apps companies, it may struggle to handle a complex fintech product like a banking or loan service.
2. Ratings and reviews. Check whether a CPA agency is listed on specialized platforms such as Clutch, Google Business, etc. These listings reflect trustworthiness, reputation, and reliability. Pay attention not just to the overall rating, but also to key details. Сheck how long the agency has been in the market and what specific case studies are mentioned. Testimonials will help you assess whether the agency aligns with your goals or not. For example, you can find our Clutch profile here.
3. Creativity. Creatives play a key role in channels like Meta Ads and TikTok Ads. You can invest a large budget. But without compelling ad creatives, you won’t get the conversions you need. That’s why it’s essential to collaborate with a CPA marketing agency. It has a skilled creative team and knows how to produce content tailored to your niche.

Before Choosing a CPA Marketing Agency, Ask Yourself the Following Questions

Below are key questions to consider before making your decision.

1. What goals are you aiming to achieve?

Define your campaign objectives and determine the desired CPA/CPI for your target actions.

2. How important is control over the process to you?

Decide whether you’re ready to fully delegate campaigns and focus solely on financial metrics, or if you prefer to stay hands-on, managing traffic sources, testing creatives, and overseeing strategy.

3. What budget are you ready to allocate?

The CPA model protects you from wasted spend and allows for relatively fast scaling. That’s why it’s important to carefully evaluate the test budgets you’re willing to allocate to an agency or traffic source.

4. Which verticals does the agency serve?

Choose agencies with proven experience and measurable success in your specific vertical.

5. What anti-fraud systems are in place?

Make sure your MMP (Mobile Measurement Partner) is properly configured. Having a mobile tracker is a must-have for running CPA campaigns in mobile app marketing.

Ready to Rely On an Agency?

At Acquisition.mobi, we specialize in promoting mobile apps through a variety of traffic channels — from Paid Social Media to OEM sources and in-app advertising. We work on a CPA model. You only pay for results: installs, registrations, or purchases.

Why Choose Our Agency?

1. Transparency & control. We work exclusively with trusted platforms. Every conversion is tracked through AppsFlyer, Adjust, and other leading MMPs.
2. Access to premium channels. Our traffic buying system enables us to reach more engaged users and boost in-app conversions.
3. Result-driven optimization. We focus on CPA-based in-app actions. Underperforming placements are cut, and only top-performing sources are scaled.

Are you looking to scale your app effectively? Contact us at affiliate@acquisition.mobi  or connect with our Head of Affiliate on LinkedIn.