Speed is everything on mobile devices. Apple knew that, which is why they plugged 64-bit chips into their new iPhones. Now, Samsung’s popular Galaxy line is getting them as well.
To take on rival Apple, Samsung has to do some serious engineering to make the 64-bit processor show end results. Switching the Galaxy over to accommodate a 64-bit chip inside the device is not trivial. There’s also the challenge in pushing most third-party developers toward a 64-bit environment when many devices still rely on 32-bit chips.