I like option 3 the best. For the "apps that are built with landscape in mind", do they only have one setting, or do they have both, but somehow work "better"

I like option 3 the best. For the "apps that are built with landscape in mind", do they only have one setting, or do they have both, but somehow work "better" in landscape? I've seen at least one of the former, but that one defaults to landscape no matter how it's oriented, so it doesn't seem like it really asks the OS for what orientation to use.