I'm religious about never, ever interrupting the user. It's unfortunate that way too many other software developers consider it acceptable. No, I don't care about your updates and onboarding and ToS changes, I opened your app with one concrete goal in mind and you're getting in my f***ing way. You aren't being helpful a tiniest bit.

If you need to inform the user about something, put a banner at the top of the screen. Or show an icon with a badge on it. Anything that doesn't require immediate attention and a context switch. Trust me, none of your stuff is so critical that the user needs to be interrupted.