The last really major new product announcement was the watch which was a while ago, so it's hard to tell. With really big projects it's hard to hide their existence, even for the military let alone a private firm, but Apple have always been very good at concealing critical details. For example we knew they were working on a web browser, phone, tablet and watch but little else until the public announcements and each came with big surprises. We know they're working on self-driving tech, but beyond that what do we really know about it?