Toronto, ON, Canada based studio Teehan+Lax has updated its iPhone 4 GUI PSD for Apple's new high-res Retina Display.

The collection of Photoshop files promises a fairly comprehensive library of iPhone GUI assets, which are all fully editable.

"It was clear as we created it that Apple has spent a lot of time considering how each element should be translated to such a dense resolution," Teehan+Lax's Geoff Teehan writes in a blog post.

"What were single pixel elements are now two or three pixels thick and effects are exaggerated to become visible. For anyone designing for the retina display (640×960) it really is quite a different experience."

As well as the iPhone 4, Apple's Retina Display is also available on the new iPod touch, introduced earlier this month.

Teehan+Lax notes, those who download the large PSD files - 62.7MB and 4074×2986 dimensions - can "pay whatcha’ like," adding "Hate it? Don’t pay anything."

The download is part of labs.teehanlax.com, billed as a showcase of "ideas and executions outside of everyday client work."

Teehan+Lax offers updated iPhone 4 GUI PSD

[Via John Nack on Adobe]