Edit: I’m a bit puzzled by the claim that Apple was selling Aarch64 before Arm had finished their first design - A7 announced at end 2013 but A53 appeared in 2012?
It looks like A53 was announced in October 2012, but I’ve found no indication of whether the design was actually finished by then [0]. And remember that ARM just sells IP and other companies are responsible for manufacturing it; it doesn’t look like anyone actually produced A53 cores until 2015 [1] — whereas Apple was shipping actual consumer products with A7’s in them by October 2013.
Very fair point. OTOH there was a lot of detailed info on the A53 available in 2013 and SoCs were being announced with it.
I suspect this thread may be slightly exaggerating the position but certainly the case that Apple were well ahead of all the competitors - and no doubt they were deeply involved in the ISA design.
Edit: I’m a bit puzzled by the claim that Apple was selling Aarch64 before Arm had finished their first design - A7 announced at end 2013 but A53 appeared in 2012?