Currently, Looptical is an iPhone app. It also runs on an iPad in 2x mode, and has been fully tested on the iPad as well as iPhone. Subjective comments from users are that the graphics look reasonably sharp in 2x mode on a Retina iPad and are not a distraction.
However, there have been a lot of requests for a Universal version of Looptical that will directly support the iPad. And potentially a lot of iPad musicians are missing out on Looptical because they would rather only run iPad apps on their iPad: an understandable view.
Because of this, the next major update to Looptical will be to make it Universal and run at Retina resolution on an iPad. At this point I don't have a release date but it is likely to be several weeks due to the large number of screens in Looptical.
In the meantime, please continue to make requests for future functionality in this forum so I can plan out updates past the Universal one.