iOS 9 will be release this fall and that is expected to bring new features and apps. iOS 9 beta is already available for developers, but the final release will happen with iPhone 6s and 6s Plus. However, if you want to download iOS 9 wallpapers before its official release, you can do it now.
Yon can download iOS 9 wallpapers for free. Just click the right button of the mouse/trackpad and hit save image. At the end of the article there is one ZIP file for those who would like to download all the wallpapers in one go. You can use these wallpapers as phone backgrounds of any smartphones.