I have an Android app built on a phone that I am going to update now to also support tablet-sized screens (in particular Galaxy Tab 10.1). I figured out the whole
Instead of fixing the orientation on the manifest, you could use
setRequestedOrientation. On the
onCreate method of each activity, check if you are on a tablet or smartphone and set the desired orientation.
Another option could be Creating Multiple APKs for Different Screen Sizes, depending on your needs.