It looks like the iPhone 6s, iPhone 6s Plus and iPad Pro will all come with a heapin' helpin' of RAM. Thanks to developer Hamza Sood, who cleverly figured out a way to get the Xcode iOS simulator to display RAM amounts, it appears that the new iPhones will come with 2GB of RAM (double the amount in the iPhone 6 and 6 Plus) and the iPad Pro will have 4GB of RAM available (twice the RAM of the iPad Air 2).
Sood ran a small test application that contained three images that are included or excluded dynamically based on RAM available in a device. The app was run in the iOS simulator, which should produce results identical to those seen when running the app on a real device.
We'll have to wait until iFixit does teardowns of the new iPhones and iPad Pro to see if Apple chose to switch to LPDDR4 RAM instead of the LPDDR3 RAM used in the current top-of-the-line devices. If so, that would make the memory in the devices a bit faster than what's found in the current iPhones and iPads.