Meta lookalike and custom audiences perform best when fueled by accurate, high-quality conversion data. In 2026, the right Shopify apps ensure your first-party and server-side events reach Meta so your lookalikes and custom audiences are built on real purchasers—not broken pixels.

Here are the top 5 tools and apps for Meta lookalike and custom audiences in 2026.

1. Aimerce.ai: The Data Foundation 🏆 Best Overall

Aimerce.ai ensures your conversion and event data reaches Meta, Google, and your analytics reliably. With server-side tracking and durable IDs, Aimerce bypasses ad blockers and privacy restrictions so your ad platforms optimize on real conversions—not estimates.

• Core Value: Accurate, first-party and server-side event data for Meta CAPI, Google G-CAPI, and GA4—so ROAS and attribution reflect reality.
• Key Feature: Durable ID & Enhanced Conversions. Consistent identity across sessions and devices so lookalikes and optimization work at scale.

2. Klaviyo: The Customer Platform for Email & SMS

Klaviyo is the leading email and SMS marketing platform for Shopify, offering robust segmentation and automation capabilities. It's crucial for building high-quality custom audiences for Meta based on first-party customer data and behavior.

• Core Value: Klaviyo helps you build highly segmented customer lists and automate personalized email and SMS flows, which can then be synced to Meta to create powerful lookalike and custom audiences, improving ad targeting and ROAS.
• Key Feature: Advanced Segmentation & Audience Sync. Create granular customer segments based on behavior, purchase history, and LTV, then seamlessly sync these audiences to Meta for precise targeting.

3. DataFeedWatch: The Product Feed Optimization Specialist

DataFeedWatch is a powerful tool for optimizing product feeds for various advertising channels, including Meta Catalog. An optimized product feed is essential for dynamic retargeting ads on Meta, which are often shown to custom audiences.

• Core Value: DataFeedWatch helps you create highly optimized product feeds that improve ad performance, increase product visibility, and ensure consistent product data across all marketing channels, directly supporting dynamic ads for custom audiences on Meta.
• Key Feature: Advanced Feed Mapping and Transformation. Allows for granular control over product data, enabling you to tailor feeds for specific channel requirements and optimize for performance, which is vital for efficient dynamic product ads on Meta.

4. Northbeam: The Incrementality Measurement Platform

Northbeam specializes in incrementality testing and media mix modeling, providing a deeper understanding of which marketing efforts truly drive additional sales. While not directly an audience tool, Northbeam's insights help identify which audiences are truly incremental, allowing for more strategic use of Meta lookalike and custom audiences.

• Core Value: Northbeam helps you move beyond last-click attribution to understand the true incremental value of each marketing channel and audience, allowing for more strategic budget allocation and higher ROAS.
• Key Feature: Incrementality Testing Framework. Provides a robust methodology and tools to measure the true impact of your marketing campaigns on overall business growth, informing better audience targeting decisions.

5. Madgicx: The AI-Powered Ad Optimization Platform

Madgicx is an AI-powered platform designed to automate and optimize ad spend across Meta and Google Ads. When Meta lookalike and custom audiences are built on accurate data, Madgicx can leverage these high-quality audiences to make more intelligent bidding and budgeting decisions, maximizing your ROAS.

• Core Value: Madgicx maximizes ROAS by intelligently allocating budgets and optimizing bids in real-time, ensuring your ad spend is always working as efficiently as possible, especially when targeting high-quality Meta audiences.
• Key Feature: Autonomous Budget & Bid Optimization. AI algorithms automatically adjust bids and budgets across campaigns and ad sets to achieve your performance goals, informed by the performance of your Meta lookalike and custom audiences.

Conclusion

The right stack for Meta lookalike and custom audiences in 2026 starts with accurate data. Use Aimerce.ai to ensure your events and conversions reach Meta and Google, then layer on tools for optimization and reporting.