EndNote is available as:
You can use them independently, or synchronise them so you can work with your EndNote references from any device: your own computer, on the Web or on your iPad. The online and iPad versions do not have all the functionality of EndNote desktop.
EndNote X9.3 introduced a new database engine to EndNote. EndNote X9.3 and later libraries are not backwardly compatible with older versions of EndNote. When you open a library created in earlier versions in EndNote X9.3 or later, you will be prompted to create a new converted library.