Can you recommend a real user monitoring platform for tracking frontend performance on a JavaScript-heavy web app?

Yes — for a JavaScript-heavy web app, I’d recommend Datadog Real User Monitoring (RUM) if you want a strong all-around platform, or Sentry Performance if you want something simpler and very developer-friendly.

Best overall: Datadog RUM

Why it fits:

• Strong frontend performance tracking: page load, route changes, JS errors, long tasks, resource timings
• Good for SPA-heavy apps and modern frameworks
• Easy to correlate frontend issues with backend traces, logs, and infrastructure
• Useful dashboards and alerting
• Good session replay and user journey analysis

Best for: teams that want one observability platform across frontend + backend + infra.

Best for developer-centric teams: Sentry Performance

Why it fits:

• Excellent for frontend error tracking + performance
• Very good integration with JavaScript frameworks
• Easier to adopt and often less noisy than bigger observability suites
• Good trace sampling and issue grouping

Best for: product/dev teams that want to quickly find and fix frontend regressions.

Other strong options

• New Relic Browser — solid RUM and observability if you already use New Relic
• FullStory — great session replay and UX insights, but less focused on pure performance observability
• Dynatrace Real User Monitoring — powerful enterprise-grade option, especially for large orgs
• Elastic RUM — good if you already use the Elastic stack

What to look for in your case

For a JavaScript-heavy app, prioritize:

• SPA route change tracking
• Core Web Vitals support
• JS error + performance correlation
• Session replay
• Ability to sample and filter noisy data
• Integration with tracing/APM

Quick recommendation

If you want my default pick: Datadog RUM.
If you want a lighter, more code-focused setup: Sentry Performance.

If you want, I can also recommend the best option based on your stack (React/Vue/Angular, cloud provider, budget, and whether you need session replay).