Cost Per Install

Mapendo Team
March 31, 2022

CPI (Cost per Install) is one of the main payout models used for Mobile App Marketing Campaigns, in which advertisers pay ad networks and DSPs for any install driven by their campaign. App install campaigns aim at acquiring users and generating installs, and that is why CPI campaigns are important. 

What is CPI?

CPI is a pricing model used in app install campaigns, which sets the price the advertiser has to pay to the publisher (DSPs, Demand-Side-Platforms, or other media sources) every time their app is installed and opened as a result of their app install campaign. So, it is different from the CPA strategy, in which the advertiser has to pay only after some post-install events performed by users (item purchase, registration and so on).

You can also obtain the eCPI (Effective Cost per Install – the actual price paid for installs) by dividing the total spending invested in the marketing campaign, by the number of app installs.
It is useful to calculate the eCPI also in a CPA campaign (where the advertiser pays the publisher only after a post-install action) to determine the corresponding price for install. This is important to estimate the Customer Acquisition Cost (CAC) and the ROAS of the app campaign.

Why is it important?

CPI is one of the most widespread payout models: let’s discover the reasons why. First of all, a CPI app campaign is safer from an economic point of view if compared to other strategies, like CPM. In fact, in this latter case the advertiser has to pay simply to show the ad, while in CPI you are sure the user has at least installed and opened your app. This is important as it helps the advertiser save money and take less risks, in other words increasing the ROAS (return on ad spend).

The second important element of success is the fact that CPI is actually a good index for your campaign, as a high number of installs means that your app install campaign was successful in targeting users. Success in installs is important also because it will lead to a higher popularity and visibility of your app in the app stores.

At the same time, we have to remember that CPI strategies may be useful for the initial steps of an app launch, to ensure more users see and install it. But for other purposes, like to increase revenues or to ensure the acquisition of high-quality users, a CPA strategy may be more suitable. In fact, despite all the advantages of a CPI app campaign and the optimization techniques, it is important to remember that users will not necessarily perform other actions after the install, like a subscription or purchase.

There are also other complex aspects related to CPI app user acquisition strategies. For example, in CPI campaigns a central element to consider is location, as the payout for a CPI varies according to the standards of a country and its population: users from a wealthier country are likely to produce more in-app revenue. CPI also depends on the channel of advertisement and the kind of app being advertised (for example casual gaming apps usually have a lower CPI). Together with this, when deciding the cost-per-install of an app install campaign, you should also look at the difference between iOS and Android users, as the first ones generally spend more than Android users: this is also related to location, as the majority of iOS users are from countries with a higher GDP.


What you need to know about CPI

  • CPI is one of the payout models in mobile app install campaigns;
  • With a cost-per-install campaign the advertiser pays the DSPs and ad networks only after the user downloads and opens the app for the first time; 
  • CPI campaigns are generally used to increase an app user base;
  • CPI depends on a number of factors such as location, kind of app, channel, and operating system;
  • Even when running a CPA campaign, it is important to estimate the eCPI (effective cost-per-install) both to evaluate the real cost paid for each install and to optimize your app user acquisition strategy.