Why Marketing Metrics Matter
Without clear metrics, you can’t scale efficiently. Performance marketing relies on data to make decisions.
1. CPI (Cost Per Install)
Definition: Cost to acquire one app install.
Formula:
CPI = Ad Spend / Number of Installs
Use CPI to evaluate:
- Channel efficiency
- Creative performance
2. CPA (Cost Per Acquisition)
Definition: Cost to acquire a paying customer or lead.
Formula:
CPA = Ad Spend / Conversions
CPA is more valuable than CPI because it reflects real business outcomes.
3. LTV (Lifetime Value)
Definition: Total revenue generated by a user over time.
Key factors:
- Retention
- Monetization
- Engagement
LTV helps determine how much you can afford to spend on acquisition.
4. ROAS (Return on Ad Spend)
Definition: Revenue generated per dollar spent.
Formula:
ROAS = Revenue / Ad Spend
Track:
- Day 1 ROAS
- Day 7 ROAS
- Day 30 ROAS
How These Metrics Work Together
- CPI tells you acquisition cost
- CPA shows conversion efficiency
- LTV defines user value
- ROAS measures profitability
Golden rule:
LTV must be higher than CPA for sustainable growth.
Common Pitfalls
- Focusing only on CPI instead of CPA
- Ignoring long-term LTV
- Not segmenting users by cohort
- Making decisions on incomplete data
Strong performance marketing depends on understanding the relationship between cost, value, and revenue. The right metrics help you scale confidently.