CPIGuides
CPI advertising: a complete guide to cost-per-install campaigns
How cost-per-install campaigns work, how installs are attributed, what drives CPI, and how to keep install quality high.
Updated August 12, 20262 min read
Cost per install (CPI) is the most common pricing model for mobile user acquisition. The advertiser pays a fixed amount each time a user installs the app and opens it for the first time.
How a CPI campaign works
- The advertiser sets up the app in a mobile measurement partner (MMP) and creates a tracking link for the network.
- Publishers promote the app using that link. Each click is recorded with a click ID.
- The user installs the app from the store and opens it. The MMP attributes the install to the click and sends a postback to the network.
- The network credits the publisher and bills the advertiser at the agreed CPI.
The "first open" matters: installs that are never opened are not counted, because nothing has been measured.
What drives CPI
- GEO — competition and user value vary widely by country.
- Platform — iOS and Android audiences differ in reach and cost in most markets.
- Category — competitive categories like finance and games typically cost more than utilities.
- Creative and store page — a better store listing converts more of the same clicks, lowering effective cost.
- Targeting — narrow targeting reduces volume but can improve quality.
Keeping install quality high
Cheap installs are only cheap if users stay. Monitor per source:
| Signal | Why it matters |
|---|---|
| Day-1 and day-7 retention | Whether installs become users |
| Click-to-install time distribution | Very short times can indicate attribution fraud |
| Post-install event rate | Whether users reach onboarding milestones |
| Device and GEO consistency | Mismatches can indicate proxies or emulators |
CPI or CPA?
CPI is ideal for launches, new GEOs and learning which sources work. As you learn which in-app events predict value, consider moving strong sources to CPA on that event. Our article CPI vs CPA covers the trade-off.
Launch checklist
- MMP integrated and tested with a real device
- Tracking link and postback verified end-to-end
- Store listing localized for each target GEO
- Traffic rules agreed (for example: no incentivized installs)
- Daily caps and budget pacing set
- Post-install events mapped for quality monitoring