I am writing an app that utilizes the use of some custom file types. I would like users to be able to download these custom file types from a website somewhere. By default, the built-in Android Browser app does not allow downloading of unknown file types, but file managers such as Astro allow files of any type to be downloaded in the Browser app. Also, I am aware that Android doesn't really care about file extensions, just MIME types.
Forcing the user to download a 3rd party app is not an option. My application must be able to provide the same type of "download freedom" that apps such as Astro do. I know it is possible because there are numerous applications that provide this sort of functionality.
I have tried all sorts of combinations of intent filters, but none of them seem to do the trick. See these questions for examples:
Register to be default app for custom file type
Register new file type in Android
Register file type for app does not work correctly
These solutions work for allowing a user to Preview the file using the GMail application, but do nothing when it comes to downloading in the browser.
How does Astro (or the other file managers) allow downloading of arbitrary file types? What is the special sauce I am missing from my manifest that will allow this?