Apple started making 64-bit smartphones last year with the iPhone 5S, but to date we've seen few tangible improvements as a result, with many developers still building 32-bit apps.
That includes any updates to existing apps, though apps that are currently available won't be removed. We imagine that not all developers will be happy about this change but it should be beneficial to users.
Using 64-bit architecture can lead to faster performance both in terms of speed and graphics and could also be beneficial to specialist applications such as those used by designers, artists and musicians which may require extra computing power.
But even if developers don't initially tap into the full capabilities of the 64-bit architecture, an environment where only 64-bit support is needed, rather than both 32 and 64-bit, will likely lead to slicker performance all round.
In the short term, apps will still support 32-bit hardware as well, but with the latest two generations of Apple hardware now on 64-bit it's likely that Apple will drop 32-bit support altogether before long and then we might see the real benefits of its 64-bit chips.
- Android is pushing 64-bit support as well.