It uses Github releases, so getting it with Obtanium should be pretty easy.

Probably not, as its not free.

No.

This is where you provide a streaming link file like m3u8 or a link to such a file and watch streaming content provided by others. For example NASA has a channel like that, so does CNN, and various other ad-supported TV network streams. There are also paid providers that require a subscription for example to access content.