In our previous blog post we mentioned that “apps have the ability to exclude the system gestures for certain parts of the screen”. The way apps do that is via the system gesture exclusion APIs, new in Android 10.
Since the behavior which the API enables is disruptive to the user, the system limits how it’s usage: apps can only exclude up to 200dp per edge.
We think that users being able to consistently go back from an edge swipe is very important. Consistently across the entire device, not just a single app. The limit may seem restrictive, but it only takes a single app to exclude an entire edge of the screen to confuse a user, leading to either app uninstalls or something more drastic.