The Cray-1 was measured on 64-bit FLOPS, so you would have to do apples-to-apples (heh). A modern iPhone can do 300 GF of 64-bit, so only 2000x.
The iPhone 4 was probably the first that could beat a Cray-1, and it was by a narrow margin. However, that was only a 32-bit chip. The next year iPhones went 64-bit, and it was all over.
There is also the issue of cooling. The iPhone will need extra cooling in order to function at full speed for more than a few minutes.
I genuinely love r/TheyDidTheMath corrections, thank you!
(now calculate it in iphone charger plug computing power heh > lunar lander)
We live in an amazing era, where the limit to what we can do is (almost?) more what we can imagine to do than what we are actually able to do.