Let's summarize
Arm yourself with events, funnels and segments! Produce as many of them as you can consistently keep in your head.
And that's it?!
Nope. Let's take a look at some tools and discuss questions
Store analytics (Apple AppStore, Google Play): competitor performance analysis, update analysis, comparison to similar projects
Moving away from Google Analytics.. Has the worst admin panel on the web, but can export data to BigQuery for further analysis
Free attribute system from Yandex
Product and behavioral analytics system, specializes in gaming apps
One of the best product analysis systems currently available (events, funnels, retention by segment and cohort analysis)
Product analytics (focuses on funnels and user session videos)
Product analytics (focuses on revenue and traffic attribution)
Stores analytics (in-store conversions, reviews, search rankings)
A convenient service for collecting install data and store (app) purchases. Pros: there's a useful API to transfer data to pretty much anywhere
A tool for visualizing and aggregating data from multiple systems. Very useful for tracking metrics on a daily basis