Product analytics platforms, compared on what actually separates them

Product analytics tools all promise funnels, cohorts and retention. The difference that matters is what they count. A tool built on sessions can tell you a page was viewed; a tool built on people can tell you who bought, what they were worth, and which channel brought them. Everything below is grouped by that distinction first and features second.

What separates a good one from a bad one

The unit of analysis
Sessions expire and cannot be joined across devices. People persist. This decides which questions are answerable at all, and it cannot be fixed later with configuration.
Revenue attribution
Whether the tool ties a dollar back to a touchpoint natively, or whether you build it yourself out of custom events and a spreadsheet.
Time to a usable report
Not time to install the snippet. Time until someone can answer a real question without help.
What the free tier actually includes
Most free tiers gate the features you need. Check whether the limit is volume or capability.

How to decide

Decide on the unit of analysis first and the feature lists second. If your questions are about live product usage, pick the strongest event pipeline you can afford to instrument, which is Mixpanel or Amplitude. If your questions are about who becomes a customer and what they are worth, pick the tool that holds the person and the revenue in one record. Everything else on these feature lists is negotiable; the unit is not, because it cannot be changed after the fact.

The last column is the honest one: when each tool, including ours, is the right choice. Where a full head-to-head exists, the name links to it.

ToolCategoryStarting priceChoose it when
KISSmetricsPerson-level analyticsFree, then $99/moThe question is who became a customer, what they are worth, and which channel brought them.
MixpanelProduct AnalyticsFree (up to 1M events/month)You need real-time product usage views and strong native mobile SDKs, and someone will own the event taxonomy.
AmplitudeProduct AnalyticsFree (limited)You are a product org with an experimentation programme and the appetite to govern a tracking plan properly.
HeapProduct AnalyticsFree (limited)You want retroactive autocapture above all, and accept session-based limits on revenue questions.
PostHogProduct Analytics (Open Source)Free (1M events/mo)You are engineering-led, want session replay and feature flags in the same box, and prefer self-serve pricing.
PendoProduct ExperienceCustom pricingYour real need is in-app guides and adoption nudges, with analytics as the supporting layer.
Google Analytics 4Web AnalyticsFreeYou need free traffic reporting tied into Google Ads, and person-level history is not the question.

Where KISSmetrics fits

KISSmetrics resolves every event to a person and ties revenue to first touch, which is the job it was built for in 2008. It is weaker than Mixpanel and Amplitude on real-time streaming and native mobile SDKs. If your questions are about product usage in the moment, they are the better fit; if they are about who becomes a customer and what they are worth, this is.

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Questions

What is the difference between product analytics and web analytics?
Web analytics counts traffic to pages: sessions, pageviews, bounce rate. Product analytics counts what people do inside the product: signed up, activated, upgraded, churned. The split matters because web analytics answers "how many came" and product analytics answers "who stayed and why".
Do I need a product analytics platform if I already have GA4?
If you only need traffic numbers, no. GA4 is session-based, so it cannot follow one person across devices and months, and it thresholds rows when volume is low. If you need to know which customers a channel produced rather than how many visits it sent, you need something person-based alongside it.
How much does a product analytics platform cost?
Most price on event volume rather than seats. Free tiers are common but usually capped in the tens of thousands of events. KISSmetrics is free to 100,000 events a month with no feature gating and no card, then $99 a month on Growth.
Can product analytics work without a developer?
Increasingly, yes, and this is the axis the market is moving on. Autocapture removes the instrumentation step for standard web events, and AI-assisted setup can assign roles to events and build the first reports. A developer is still needed for server-side events and for custom properties that only exist in your backend.
What is the difference between Mixpanel and Amplitude?
Less than either would like. Both are event pipelines with strong funnels, cohorts and experimentation, priced on volume, and both reward a well-governed tracking plan. Amplitude leans further into enterprise data governance, Mixpanel into speed for smaller product teams. Teams switch between them far more often than they switch away from the category.

Comparing two specific tools? Every head-to-head comparison.

KISSmetrics

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