Developers are signaling that Apple has just issued the fourth beta of the iPhone 3.2 software and SDK. Available as a free download for those enrolled with the company’s iPhone Developer Program, the package contains both the latest build of the iPhone OS 3.2 for iPad, and the iPhone SDK 3.2, for iPad development.

According to a screenshot posted over at 9to5mac, iPhone SDK 3.2 beta 4 requires Mac OS X 10.6.2 or later (meaning Apple has already tested the software against current 10.6.3 builds). The Mac maker further asks developers to note that iPhone SDK beta 4 is for development purposes only, and should not be used for submitting applications to the App Store. Finally, since iPhone SDK 3.2 beta 4 is pre-release software, Apple labels it as “confidential,” which extends to everything contained in the package developers are required to download.

“This is a pre release version of iPhone SDK 3.2 beta to support development of applications for iPad devices. Please review the Release Notes and Read Me before installing this beta software release,” Apple tells registered developers. Posted on March 9, 2010, downloads are available for “iPhone SDK 3.2 beta 4 with Xcode 3.2.2 (Snow Leopard);” “iPhone SDK 3.2 beta 4 Release Notes;” “iPhone SDK 3.2 beta 4 API Diffs;” “Xcode 3.2.2 Read Me.”

In related news, the company headquartered in Cupertino, California has recently updated its Dev Center to include some changes regarding price, benefits and new terms and conditions. Formerly starting at $499/year, the new Mac developer program is now attractively priced at just $99. “Receiving pre-release Mac OS X software is an exclusive benefit for all Mac Developer Program members and allows developers to begin incorporating the latest technologies into their development process, test for compatibility, and report bugs,” Apple said earlier this month, addressing future Mac OS X testers. Enrolled iPhone developers are required to update their profiles, take a survey and agree to new terms, if they haven’t done so yet.