PostHog
Open-source product analytics. Feature flags, session replay, funnels, heatmaps, all Mixpanel features for free.
Strengths
- Open code (MIT): cloud version (EU or US) or self-hosting if you want control over the data
- Feature flags, A/B tests, surveys, heatmaps, all Mixpanel + Amplitude free
- Integrated session replay: review every session without third-party tool
- 1M events/month free, sufficient for most early-stage products
Limitations
- More complex UI than Plausible, long onboarding for non-devs
- Self-hosting is no longer officially supported and needs a serious machine (4 vCPUs, 16 GB RAM recommended)
- Session replay retention limited on the free tier (30 days)
Best for
- Early-stage SaaS: understand user journeys without analytics budget
- Products using feature flags for progressive rollouts