PostHog

PostHog is an open-source Product OS for product engineers, product teams, and data teams who need one place to build, test, measure, and improve digital products.

Key capabilities include:

• Product analytics with funnels, trends, paths, retention cohorts, stickiness, and lifecycle analysis, plus autocapture for clicks and pageviews and retroactive event definition.
• Session replay for web and mobile, including console logs, to investigate user behavior and debug issues.
• Feature flags and experiments (A/B testing) to ship changes safely and measure impact.
• Data stack tools such as a data warehouse, HogQL SQL editor, BI and visualizations, and 120+ sources/destinations for integrating external data (including Stripe).

Pricing: Freemium with usage-based, pay-as-you-go pricing and generous free tiers (for example, 1M events/month for analytics and 5,000 recordings/month for session replay). The self-hosted open-source version is free.

Notable for combining analytics, replay, flags, experiments, surveys, heatmaps, web analytics, warehouse, SQL, and AI features (including LLM analytics and an AI product assistant) in one platform, with both cloud and self-hosting options and SDK support for iOS, Android, React Native, and Flutter.