PostHog
An open-source product analytics suite with event tracking, funnels, retention, session replay, feature flags and surveys, and a generous free tier. It shows you where users drop off between sign-up and paying, which is what an early product most needs to know.
Tool
Web Development
PostHog
An hour to install
Intermediate
Free
What it is
PostHog is a product analytics platform that you add to a web or mobile app with a small SDK. It records events such as "signed up", "created first project" and "started trial", then lets you build funnels, retention charts and user paths. It also includes session replay, feature flags, A/B tests, surveys and error tracking, so one tool covers most of what a small product needs.
Why product analytics matters early
Page-view analytics tell you how many people visited. Product analytics tell you what they did next: how many signed up, how many reached the moment where the product becomes useful, and how many paid. Those numbers, activation and conversion, decide what you fix first. Without them you guess.
Free tier (as of 2026-09)
PostHog's pricing page lists a free plan with no card needed, with monthly allowances including 1 million analytics events, 5,000 session recordings, 1 million feature flag requests and 1,500 survey responses. Beyond that it charges per unit of usage. Most early products stay inside the free tier.
How to use it well
- Define five to ten events that match your funnel: visit, sign up, activation event, trial start, purchase.
- Build one funnel chart from sign-up to payment and look at it every week.
- Watch a few session replays of people who dropped off. It is humbling and useful.
- Ask a one-question survey to users who cancel.
Privacy
Tracking users brings obligations. Tell users what you collect in your privacy policy, avoid recording sensitive fields in replays (PostHog can mask inputs), and follow consent rules where they apply, such as for visitors in the EU.
Common questions
Is it open source? The core is open source and can be self-hosted, but the hosted cloud is simpler for a small team.
Do I need it on day one? Add it before launch, so launch-day traffic gives you real data.
Source: posthog.com/pricing, checked 2026-09.
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