PostHog

PostHog is an open-source product platform that bundles product analytics, session replay, feature flags, experimentation, surveys, error tracking, and a data warehouse into one tool, available as cloud or self-hosted. The problem it targets is stack sprawl. A typical product team wires up Mixpanel or Amplitude for analytics, LaunchDarkly for feature flags, FullStory or Hotjar for session replay, Sentry for errors, and Typeform for surveys - five contracts, five SDKs, five sets of user identities that do not join up. PostHog's bet is that these are all the same data, so they belong in one product where you can watch the session replay of the user who dropped out of the funnel, behind the feature flag you shipped last week. Pricing is usage-based with a large free tier, and PostHog states that more than 90% of its customers use it for free. The monthly free tier resets every month and applies on every plan, including paid ones: 1 million analytics events, 5,000 session recordings, 1 million feature flag requests, 100,000 error tracking exceptions, 1,500 survey responses, 1 million data warehouse rows, 10,000 pipeline events, 100,000 AI observability events, and 10 GB of ingested logs. No credit card is required, and the free plan includes 1 project, 1-year data retention, unlimited team members, and a choice of US (Virginia) or EU (Frankfurt) hosting. Past the free tier, pricing is per unit and the rate falls with scale. Product analytics starts at $0.00005 per event for the first 1-2 million events beyond the free tier, dropping through $0.0000343 (2-15 million), $0.0000295 (15-50 million), $0.0000218 (50-100 million), $0.0000150 (100-250 million), to $0.0000090 per event above 250 million. Adding a card also raises the account to 6 projects, 7-year data retention, and email support. Per-product billing limits can be set so a traffic spike cannot produce a surprise invoice. Who it is for: engineering-led product teams, especially at startups, who would rather instrument once and get five tools than integrate five vendors. Self-hosting suits teams with data residency constraints, though PostHog's EU cloud region covers most of that need without the operational burden. How it compares: Mixpanel and Amplitude are more refined as pure analytics products and are the better choice if analytics is all you need. LaunchDarkly is a stronger standalone feature-flag platform with more governance. Sentry is a better error tracker. PostHog rarely wins any single category head-to-head - it wins on consolidation, price at low volume, and the fact that the tools share one user identity. Evaluate it when you are about to buy your third point solution.