What is Cost Per Install?
Cost Per Install (sometimes referred to as CPI) campaigns are specific to mobile apps and the advertiser only pays once the app has been installed (instead of been simply viewed like in other advertising metrics such as CPM).
Depending on the Demand Side Platform or Ad Server running the campaign, the Cost Per Install value can be set as the KPI or could used as a post campaign metric. Cost Per Install is usually set as a dollar value, for example $7.50.
In a Cost Per Install campaigns are pretty much run like a Cost Per Acquisition (sometimes referred to as CPA) where the conversion trigger is the installation of the Mobile App by the end user.