This is the 3rd episode of “The Zen of Monetization”.
It covers three principles for users’ retention:

• Understand user behavior in your app.
• Identify roadblocks to retention (e.g screen tracking and events).
• Use tactics & tools to re-engage users (e.g. use a specific method to specific users’ segment).

Slides

The longer version can be found in this post on retaining users.
Enjoy.