什么是 re-engagement 再营销？
In mobile marketing, re-engagement refers to an advertisement targeting a user that has been using an advertiser's app or playing their game, but becomes inactive or dormant. The main idea of such an ad is to motivate this user to become active again.
为了召回用户，营销人员通常在 Cost Per Re-engagement（CPE，重安装成本）的基础上开展特殊的再营销活动。
再营销广告的目的是什么？
Re-engagement advertisements are shown to "dormant users" to engage them in the app again before they uninstall it and become "lapsed users."
为什么再营销重要？
It is important to "wake up" dormant users before they uninstall an app. Keeping the audience engaged helps to increase conversion rates and get a higher ROI 投入产出分析. As such, users are more likely to take action inside an app. It's usually cheaper to engage an existing user than to attract a new one.
如何重新吸引休眠用户？
首先，重要的是要了解为什么以及在什么阶段，用户可能会变得不活跃。这通常是由多种不同的原因造成的：用户可能被卡在游戏的某个关卡，不知道下一步该做什么；应用经常崩溃，某个操作太复杂，或者使用体验很差；或者他们可能已经开始使用（或玩）另一个应用程序，等等。记住：交互体验至关重要。
重新吸引不活跃用户的最常见方法是发送推送通知，通知他们问题已经解决，为他们提供额外的生命或奖金，或功能更新等。也可以是提供折扣，提醒用户错过了某些内容，或突出显示一个特殊功能。
Re-engagement vs retargeting in mobile marketing: what's the difference?
在移动营销中，再营销和重定向广告之间的区别在于，再营销用于激活休眠用户，而重定向用于吸引之前对应用程序表现出兴趣的潜在用户或成为失效用户的用户。