Apple iPhone SDK 4.0 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The application lies within Developer Tools, more precisely General. According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software.
From the developer:
Apple iPhone SDK... The iPhone Developer Program provides a complete and integrated process for developing, debugging, and distributing your free, commercial, or in-house applications for iPhone and iPod touch. Complete with development resources, real-world testing on iPhone, and distribution on the App Store, you have everything you need to go from code to customer.
You may want to check out more software for Mac, such as Apple Configurator, Notes by Apple Inc. or Calendar by Apple Inc., which might be similar to Apple iPhone SDK.
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