Google is rolling out a new app campaign type to remarket to existing users. Starting this year, app campaigns for engagement will also be able to include a custom prompt from users when shown in Search.
These campaigns can feature new offers and content to bring back users who haven’t used your app in awhile, have products in their care or are likely to make a purchase. This is an automated campaign type which serves ads dynamically on Google properties. These campaigns can also be linked to data or products feeds from Google Merchant Center.
To be eligible for this campaign type, your app needs an audience size of at least 250,000 installs.