06.1.3 · Skill in Product instrumentation
Identity resolution
Linking anonymous and logged-in activity to the same person.
Users browse anonymously, sign up, switch devices and share accounts. Identity resolution stitches those sessions together. Getting it wrong inflates user counts and breaks funnels at exactly the signup step you care about.
Resources
2- docsStart hereIdentifying users ↗PostHog docs · 15 min
Shows exactly when to call identify, how anonymous events get merged, and the mistakes that split one person into two.
- docsGo deeperIdentity resolution ↗PostHog docs · 12 min
Treats identity as an engineering problem across browser, mobile, server and third-party data, which is what it becomes in practice.
Tools
2- ToolOpen sourcePostHog
Open-source product analytics with session replay, feature flags, experiments and surveys in one tool.
- ToolFreemiumTwilio Segment
Collects events once and sends them to analytics, marketing and warehouse tools, with tracking plan enforcement.