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description: Product analytics - usage tracking, feedback loops, crash reporting, iteration signals for any app type
mode: subagent
tools:
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---

<!-- SPDX-License-Identifier: MIT -->
<!-- SPDX-FileCopyrightText: 2025-2026 Marcus Quinn -->

# Product Analytics - Data-Driven Iteration

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## Quick Reference

- **Purpose**: Track usage, gather feedback, monitor crashes, drive iteration
- **Tools**: PostHog (open-source), Sentry (crashes), RevenueCat (mobile revenue), Plausible (web)
- **Principle**: Measure retention and revenue, not vanity metrics
- **Applies to**: Mobile, browser extensions, desktop, web apps

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## Analytics Stack

Open-source preferred. All self-hostable on Coolify — see `tools/deployment/coolify.md`.

| Tool | Purpose | Notes |
|------|---------|-------|
| **PostHog** | Product analytics, feature flags, session replay | Self-hosted or free cloud |
| **Sentry** | Crash reporting, error tracking, performance | Self-hosted or free cloud |
| **Plausible** | Privacy-friendly web analytics | Self-hosted or paid cloud |
| **Umami** | Simple web analytics | Self-hosted or free cloud |
| **RevenueCat** | Subscription analytics, cohort analysis | Mobile (iOS + Android) |
| **Firebase Analytics** | Event tracking, user properties | Mobile + web |
| **Expo Analytics** | OTA update adoption, crash rates | Expo apps |

Platform dashboards: App Store Connect (iOS), Google Play Console (Android), Chrome Web Store, Firefox Add-on Statistics.

## Key Metrics

### Retention (most important)

| Metric | Target | Action if below |
|--------|--------|-----------------|
| Day 1 | > 40% | Fix onboarding |
| Day 7 | > 20% | Improve core loop |
| Day 30 | > 10% | Add engagement features |

### Engagement

- **DAU/MAU ratio** — stickiness (> 20% good)
- **Session length / frequency** — time spent, return rate
- **Core action completion** — users doing the main thing

### Revenue (if monetised)

- **Trial-to-paid** — paywall effectiveness
- **MRR / ARPU** — business health
- **Churn / LTV** — subscriber loss, long-term value

RevenueCat provides most revenue metrics for mobile. Web/desktop: Stripe dashboard or custom analytics.

### Quality

| Metric | Target | Tool |
|--------|--------|------|
| Crash-free rate | > 99.5% | Sentry |
| Launch/load time | < 2s | Performance monitoring |
| API error rate | < 1% | Sentry / custom |
| Store rating | > 4.5 stars | Store dashboards |

## Feedback Loops

- **In-product**: Rating prompt after positive experience (not randomly). Low-friction feedback form in settings. Feature request upvoting. Bug reports with automatic context (device, OS, screen).
- **Store reviews**: Monitor daily (automate with store APIs). Respond to negatives with solutions. Track common themes to prioritise features.

## Iteration Cycle

Identify metric below target → hypothesise cause → design experiment (A/B or feature change) → implement and measure → keep winner, iterate on losers.

## Implementation

- **Event naming**: Track actions not screens — `verb_noun` (e.g., `complete_onboarding`, `purchase_premium`). Include relevant properties (duration, count, category). Don't over-track — focus on decision-informing events.
- **Privacy**: Respect App Tracking Transparency (iOS). Provide analytics opt-out. Avoid PII unless necessary. GDPR/CCPA compliance. Prefer privacy-friendly tools (PostHog, Plausible).

## Related

- `product/monetisation.md` - Revenue analytics
- `product/onboarding.md` - Onboarding funnel optimisation
- `product/growth.md` - Acquisition metrics and channel attribution
- `tools/deployment/coolify.md` - Self-hosting analytics
- `services/analytics/google-analytics.md` - Web analytics (GA4)
- `services/monitoring/sentry.md` - Error monitoring
