I think a future upgrade for the site is definitely user accounts and a charge to remove ads and/or pay for premium features, leaving the basic information free for common users with more modest needs.
One advantage of a user account is you can begin to set favourites/bookmarks (I realise you can literally just bookmark, but that's not quite the same) so you can access the same things on multiple devices.
I bought the Android app many years ago, but don't know how many others did (Play store says 5,000+ installs). I think people will pay for premium features. What they like less is anything obtrusive that 'spoils' the user experience. Even a tiny delay for something like checking realtime information can frustrate, which is almost certainly an overreaction - but we're used to clicking on something and getting instant gratification. If you can't get that platform number quickly, you'll feel the service is less useful and may well try something else.
Of course, developing such things costs a lot of money and I can't say for sure that a lot of people would pay (and I'd likely prefer to pay a one off fee than a monthly/annual sub) so I don't pretend to have a solid business plan.