In the Apple Store, there is a note-taking app called Notability. It acts as a PDF annotator, recording app, with the ability to connect with third-party apps such as Dropbox, Google Drive, Chrome, among others. I currently have an iPad, and I have found that this app is infinitely useful for school, but the iPad as a whole is not. There is no plain word processor, no USB capabilities, no mouse, and accessories are generally pretty expensive. In a few months, I want to make the move to either an Android or Windows tablet ( I have an AT&T Samsung Galaxy S3 right now and love the Android operating system), but neither of them have any app on the market as good as Notability.
My question is this: is there any way that an Apple app could be put on to a tablet running on a different operating system, and if so, how would one go about doing it?