Expected behavior
If I use the WordPress app with a self-hosted site, I expect to be able to share to the app when it comes up as a sharing target on my device.
Actual behavior
The share extension was implemented first for WordPress.com/Jetpack sites (see #2231 and #4928). It is not yet available for self-hosted (non-Jetpack) sites — instead I am prompted to log in to a WordPress.com or Jetpack site.
Screenshot

Tested on iPhone 6, iOS 10.2.1, WPiOS 6.8