Facebook advertising cost: Everything you need to optimize your ROI
Sprout Social
SEPTEMBER 6, 2018
For example, boosting a post for engagement still creates a subtle Like button that users can click. You’ll only get charged for the post engagement. Cost Per Mille (CPM) : Cost per 1000 impressions. An app install often costs more than a post engagement because it requires more buy-in from the user.
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