To me it’s like any battle between centralized and decentralized discussion (whether IT staffing or websites and multiple domains)…truth is in the middle
I think all in one apps can work well for say a city in the way of a portal.
If there is a killer use case, like in U.S. TSA and their screening app which isn’t just a TSA app but all about boarding airplanes. Or SSA Baby Name app which isnt about retirement benefits but about baby names, then I like a separate app.
Additionally, I think a big key in the end is promotion. Even if a good app, you got to really market it to get downloads.