Some things to consider in deciding if you are going to create separate Facebook pages for each app.
1. Do you or your brand already have a fanbase? For example, Facebook brand has a following and people already trust them. They can release an app under their own name and it will get downloaded and tested. (plus they have a beta community).
Do you have a known and trusted brand already?
2. Do all of your apps fall into one category? Are they all games or productivity apps or are they all in a theme. On the other hand, do they vary widely? One is a game and one is a productivity app?
Given a well known brand and common theme to the apps, I think one page for all is a better idea. The audience who uses one will be interested in others. This will make it easier to promote other apps as you create more.
Alternatively, if each app is a separate entity and will be used by a different customer avatar, it might make sense to have a page for each app.
Another approach is to name the page about what the app does or problem it solves.
You might have a “brand page” names Amazing Apps Company. This is where you post news about your company, upcoming releases etc.
Additionally you could have a page about the problem your app solves or something around the function of the app. You page might be called “Productivity Hacks” and this is where you promote your productivity apps. The page name tells people a bit about what the apps do and problem they solve. This is more attractive than a generic “Amazing Apps Company”.
For a real world example:
Nintendo has a brand page. You can see that each major sub brand or game has it’s own page.
Pokemon Go has it’s own page, because it is so popular and really has it’s own audience.
So really it depends if you are one overarching brand or if each app might have it’s own fanbase.