Does anybody know whether Skylanders bought for PS3 will work on other platforms as well? Or are Skylanders platform specific?
Generally speaking, the Wii, Wii U, PS3, and PS4 Portals are all interchangeable. It is only the Xbox 360 and Xbox One Portals that are console specific. If you're still confused though, take a look at the compatibility charts in the link below.
You've probably already gotten an answer, but I figured for those looking at this way late (myself a year behind the curve apparently) that I'd share this link: https://skylanderscharacterlist.com/getting-started/figure-compatibility/ It looks like the characters can be used on all platforms, portals are a different story.