i developed an app that contains a lot of activities and different application within the same app and they are all interconnected by sending different intents within it to function the whole app, however they still do different things and i can elimante one without hurting the other and causing the whole app to crash. so if i want i can divide them to be stand alone apps.
My question is this:
Can i have one app that download the basic activities and if a person want a specific activity they can download it (Eg: you download a game and that game includes a different set of levels that can be downloaded by pressing a button hence downloads that particular set of levels.)?
Forgive me if I misunderstood you, but are you talking about creating one big app that consists of many smaller apps, but rather than being all bundled in the beginning, a user can download each one as a module?
If it's this, it's not impossible, but not possible in the sense that I think you're hoping for.
Your one big app will still need all the necessary code and xml files because these need to exist when compiling. But what you can do, which is similar to what games do is to offer downloadable content that isn't code. Essentially, these are resources such as media files, text, or other data of the like.
Those data can be downloaded separately without affecting your app and it helps reduce the size of your app. However, the actual functionality of each individual app will still need to be within your app, but hidden until it's downloaded.
Typically, it's more common to just bundle it all together such as a Measurements app, or to have them as individual standalone apps such as Google Docs, Sheets, and Slides.