PostHog

PostHog measures what people do inside your product or site: which pages they visit, where they drop off and what they click. It also offers session replay, feature flags and surveys. It suits a solo founder with a web app or product site who wants to learn from real usage. If you run a simple brochure site, a lighter analytics tool will do.

PostHog uses usage-based pricing for each product, with no minimum spend. On the maker's pricing page, the monthly free allowance is 1 million analytics events, 5,000 session recordings, 1 million feature flag requests and 1,500 survey responses, and 1 million data warehouse rows. No credit card is needed to start. You can set billing limits on most products so you do not get a surprise bill.

• Start free and watch your usage for a month.
• Set a billing limit before you add a card, then raise it only when the data justifies it.

• Create a project and add the tracking snippet or SDK to your site or app.
• Define the three or four events that matter, such as sign-up, first action and payment.
• Build one funnel from visit to payment and check where people leave.
• Watch a handful of session replays each week to see what confuses people.

Usage-based bills need watching as traffic grows. The tool has many features, which can overwhelm a beginner, so use only what answers a question you have. Tell visitors what you track in your privacy policy, and respect consent rules that apply to your audience.

Plausible and Fathom are simple, privacy-focused website analytics. Google Analytics is free but heavier. For error tracking rather than behaviour, see Sentry.

PostHog covers product analytics in the Lean SaaS Founder stack.