Yes, yes you can use multiple devices. We allow you to suffer with one account across multiple devices.
We allow up to five connections with one account. This means your one account could be connected to a iMac, MacBook Pro, Windows Computer, iPhone, and iPad all at the same time. We don't think you would want that much suffering all around you at the same time, but you have the ability to stay on all of those devices at once without logging out.
Above is an example of 4 accounts all logged into an iMac, iPad, MacBook Pro, and Windows Surface 4.