How to embedded applications on android?

Question

Hi,

I am planing to create an host application (let say game library) and make new applications which can be downloaded and run in the host app.

Let say, I have an Host application named GameBox and this works like library for all my game applications. When any user installed the GameBox, he will see the list of all available games. And, if he wants, he will be able to download the game and run in the GameBox directly.

When I seached about this point, I see some Widget technique. Is the Widget is my total answer or is there any other option?

Best...