Interesting observation, on an recent "international" (Puerto Rico to Canada) itinerary, I got boarding passes from a kiosk at LAX. I then downloaded the UA app on my phone, and for whatever reason, electronic boarding passes never appeared on the home sceeen of the app. This was different than my previous experience, where I could access electronic boarding passes (in the app) from the home page even after retrieving them in person. Also my flights never showed up automatically in flight status area of the app.
While I could still get my boarding passes from Trips area of the app, I was hoping to get them on the home screen of the app. I was on a separate itinerary heading into Puerto Rico, and due to delay, was hoping to get some real time notification of the UA flight, such as actual start of board time.