And? These are available on google, on the airline's website, and on screens throughout the terminal. Many airlines will send them to you via SMS. There's no need to have a whole app just to check your gate assignment.

Or I could just use an app and get a push notification.

If you have a half gig spare for such an app these days maybe

I can't remember the last time I received a gate change notification via SMS. App push notifications are more common in my experience.