TENAA, Geekbench confirm that there is 3GB of RAM on the Apple iPhone 7 Plus
Throughout the year, there had been rumors that the latest 5.5-inch iPhone phablet would see a 50% hike in RAM to 3GB. This number can not be compared to the amount of RAM used on an Android phone, which ranges these days from 2GB to 6GB. Because of the optimization used by Apple with iOS, it takes less RAM for the iPhone to run smoothly. The Apple iPhone 7 continues to carry 2GB of the sweet stuff.
The A10 fusion chipset that powers both new iPhone models has four cores. The two energy efficient cores used for light housekeeping (like checking email) are slower in order to save on battery life. The other two cores are high performance and run 40% faster than the A9. Those are the two cores employed on Geekbench, where the iPhone 7 Plus scored 3233 for the single core test and 5363 for the multi-core test.
source: TENAA, GFXBench via 9to5Mac