Keen eyed observer and Twitter user Frank has noticed that there are some additional ‘2x’ images in the Twitter framework of iOS 5. Those images clock in at 2048×1536, double the current resolution of the iPad 2. This is sparking rumors that we may see a Retina display in the next generation of iPad.

TweetSheetiPadVignettePortrait 520x693 High res images in iOS 5 spur rumors of Retina display in iPad 3

A '2x' 1536x2048 image, discovered in the Twitter framework of iOS 5

This isn’t the first time that we’ve seen these double-size images as they showed up just before the iPad 2’s release in the iOS 4 beta. Despite those images appearing, the iPad 2 did not have a Retina display. This leads us to take the discovery of these images as an indication that Apple is testing a higher-resolution iPad in the labs, but that does not necessarily constitute proof that we may see a Retina display in the iPad 3.

The iPad 3 has been rumored to be released later this year, shifting the iPad to a Summer release schedule, rather than one early in the year.