Some games are shown in PlayStation Store as being ‘crossplay’. These games can be downloaded and played on different types of PlayStation systems. For example if you download a game to both to your PS Vita and PlayStation 3, you can play it on either system. With online storage, you can save your progress on one system and then continue on the other system later.
If you have Automatic Update activated on your PlayStation system your game saves will automatically save PlayStation Network ready for you to pick up on any PlayStation 3.
Make sure to deactivate your friend’s PlayStation 3 from your Sony Entertainment Network account to ensure you do not reach your activation limit.
For information about using online storage with PlayStation Now see the dedicated PlayStation Now article.