The PlayStation 4 doesn't support traditional backward compatibility. Shove a Fallout 3 disc into your PS4 Pro, for instance, and nothing will happen. This is due to the custom Cell processor that Sony used in the PS3. It was a capable but notoriously difficult chip for developers to work with, and the company wisely chose to switch to the more common x86 architecture for the PS4 in 2013. Sony has cracked PS2 emulation, however, and currently offers a small selection of classics in the PlayStation Store.
As a result, on the PS4, PlayStation Now only offers downloads for PS4 and PS2 games. Everything from the PS3 era has to be streamed over a Sony-controlled server. (If you're on PC, the entire service is streaming only.) I tried the critically acclaimed Ico (the HD remaster that was released for the PS3 in 2011, not the PS2 original) over my admittedly ropey home broadband connection. PlayStation Now tested my setup, however, and deemed it acceptable for game streaming. In theory, then, my experience should have been as Sony and the participating developers intended.
Ico worked well enough, and I was immediately captivated by the atmospheric puzzler crafted by Fumito Ueda in 2001. It helped, of course, that the slow-paced adventure didn't require precise platforming or ninja-like reactions to defeat its shadowy monsters. I did notice the occasional slow-down and dropped frame, but there was no perceptible input lag.
Buoyed with confidence, I tried Sonic Generations, a blazing-fast mixture of 2D and 3D stages. I charged through the first couple of levels with a grimace, rather than a Cheshire cat grin on my face. Something about the platforming felt a tad off. A short delay, perhaps, between my thumb hitting the X button and watching the blue blur launching himself over a chasm of game-ending spikes. I was suddenly aware that my eyeballs were watching a feed, rather than a game running natively on the PS4.
To verify these feelings, I downloaded two PS4 games through PlayStation Now: Steep, an extreme sports title that was recently given away as part of PS Plus, and Adventure Time: Pirates of the Enchiridion, a family-friendly game based on the Cartoon Network phenomenon. The process took considerably longer than starting a new stream, of course. But no longer than a game would normally take to download after purchasing it through the PlayStation Store. Unsurprisingly, both games ran beautifully. I quickly dumped more than a dozen hours into Steep, descending both Alaska and the Alps via snowboard, wingsuit and paraglider. Likewise, I was soon swept up in the colorful adventure featuring Finn, Jake and Marceline.
The flawless performance made me think of Xbox Games Pass, a subscription service that leverages the true backward compatibility of the Xbox One. There's no way that Sony can match this, of course. But it could aim for a similar breadth and quality of current-gen titles. Xbox Games Pass offers every Microsoft exclusive on the same day that it hits store shelves. Meanwhile, I have no idea if the God of War reboot, Detroit: Become Human and Insomniac's Spider-Man will ever come to PlayStation Now.