Apple today rolled out the latest iteration of iOS 4 and made a surprising retraction of its policy requiring all developers to use its developer tools.

The new version of iOS 4 was featured in last week’s presentation of Apple’s latest line of iPods. It includes minor updates, bug fixes and Game Center, Apple’s new gaming portal.

But beyond advancing its mobile OS, Apple says it has taken into consideration feedback from its developers that resulted in a relaxing of its rules concerning the use of third-party developer tools so long as the resulting apps “don’t download code.”

The move would allow developers to create apps in languages such as Adobe’s CS5, which seemed to be at the heart of Apple’s banning third-party developer tools back in April.

In addition to allowing outside source code, Apple has published App Store Review Guidelines, which it hopes will help developers “understand how we review submitted apps.” The company went so far as to acknowledge that it needs to be more transparent in its guidelines.

“We hope it will make us more transparent and help our developers create even more successful apps for the App Store.” the release states.

In April, Steve Jobs penned an open letter entitled “Thoughts on Flash,” which seemed to tie-in with revisions to Apple’s developer guidelines that banned third-party platforms for creating applications. In that letter, Jobs wrote that “letting a third party layer of software come between the platform and the developer ultimately results in sub-standard apps and hinders the enhancement and progress of the platform.”

“If developers grow dependent on third party development libraries and tools, they can only take advantage of platform enhancements if and when the third party chooses to adopt the new features,” Jobs wrote, adding that Apple cannot be “at the mercy of a third party” deciding if and when they will make Apple’s enhancements available to Apple developers.