Xcode currently supports three different device architectures: armv7, armv7s, and arm64. The former are 32-bit architectures and the later is obviously 64-bit. Up until Apple introduced App Thinning and bitcode, all three of these architectures would be packaged with your app, which roughly tripled the size of app binary.
Today, 32-bit devices are nearly a thing of the past, which raises the question: when will 32-bit go away altogether? The below pie charts summarize the current state of affairs with regard to 32-bit device usage.
The last iPhone released using a 32-bit architecture was the iPhone 5 in September 2012; the last 32-bit iPad was released in October 2012. Note that I’m not counting the iPhone 5c, which was released in September of 2013, since it was adopted at a substantially lower rate than the similarly positioned iPhone 5. Check out our data site for the exact numbers.
Xcode disabled armv6 compilation in September 2012. The last phone released that used the armv6 instruction set was the iPhone 3, which was released in July 2008.
What does this mean in terms of discontinuing 32-bit support? Apple disabled armv6 builds in September 2012, four years after the iPhone 3 (the last armv6 device) was released. Given that it’s been four years since the last 32-bit iPhone, it seems like a ripe time to put the kibosh on 32-bit builds. I’m going to go out on a limb and predict it will happen at this year’s WWDC.
If my prediction proves correct, it would mean that consumers using devices earlier than iPad Air and iPhone 5s would stop getting app version updates when developers switch to using the new Xcode. Why would Apple take this risk with over 50% of iPad users still on 32-bit devices? Firstly, it may incentivize people to upgrade. Secondly, Apple would be able to discontinue their 32-bit flavor of iOS, which would reduce their development costs.
An interesting aside: There are quite a few older iPad devices out there. It’s always seemed to me that one of the reasons for Apple’s slowing iPad sales is not due to lack of consumer interest, but because of the fact that the product lasts forever. My iPad 2 is still kicking and it’s four years old. That’s longer than I’ve had most computers.