Only in August 2023 official information is available about the technical specifications or features of the iPhone 15 or any subsequent models. However, we can expect some potential differences if we compare the iPhone 14 Pro Max and the iPhone 15 based on previous Apple release patterns.

In terms of design, Apple tends to make incremental changes between models, so the physical appearance of the iPhone 14 Pro Max and iPhone 15 may be similar. However, there could be improvements in materials, finish, or dimensions.

Regarding hardware and performance, the iPhone 15 might feature a more advanced processor, possibly an even faster and more power-efficient chip compared to the iPhone 14 Pro Max. Additionally, the camera system might see enhancements, including improvements to sensor technology, image processing capabilities, and potentially new features aimed at improving photography and videography experiences.

Software-wise, the iPhone 15 would likely run the latest version of iOS, offering new features, enhanced privacy settings, and a more refined user interface.

Please note that the information provided is speculative, as the iPhone 15 has yet to be released at the time of my knowledge. It's always better to refer to Apple's official announcements or website for the most accurate and up-to-date information regarding their products.

The expected sale date shall be September 2023.