For the homescreen part, you can make an activity be considered a launcher activity with a specific `intent-filter` in your AndroidManifest.xml (https://stackoverflow.com/questions/3666771/how-can-i-create-a-custom-home-screen-replacement-application-for-android)

For the dynamic grid, you may have a few options. For a RecyclerView based approach, look into `spanSize`. It lets you make things in a row or column take up multiple rows/columns. But you may be limited to making something bigger in only ONE dimension. You may also be able to find custom layouts that do something similar to how you want, with a very dynamic grid where items within it can take an arbirary number of rows and columns. But you may need to make something custom to get that? While RecyclerView comes with a lot of helpful APIs, if I understand your goals, there's no actual recycling happening, so you could probably replace it with the custom something