Stockfish for iOS does, and I am sure there are many others.M ANSARI wrote:I do think that 64bit hardware will help tremendously in chess, but is there any engine designed for Android or Apple OS that runs in native 64 bits?
Actually it is completely trivial to do: All you have to do is to tick off a checkbox and inspect and eliminate a few compiler warnings. The whole process took about 5 minutes for Stockfish.I think there would need to be new compiles specifically for 64 bits and not sure if Apple would accept as that would make the application void for basically all previous versions of hardware. I guess you could have the application with both 32 and 64 bit code, but maybe that would be very tricky to do.
The result is what Apple calls a "fat binary", which basically means two binaries for two different architectures merged into one. It's not a new technology, Apple did exactly the same during the transition from PowerPC to x86 CPUs in the Macintosh.
Of course, fat binaries are bigger, but for most applications, the binary size is just a tiny fraction of the total application size anyway. It's the data (in Stockfish's case, the opening book and the built-in PGN databases) that consumes disk space.