- Set the “Architectures” build setting to
armv7, which is 32-bit.
arm64for 64-bit, and
$(ARCHS_STANDARD)default is probably “64-bit if available, 32-bit otherwise”.
- According to [Wikipedia], all 32-bit devices have been discontinued, but several older ones target iOS 9 & 10, so anyone supporting iOS 9/10 is implicitly supporting 32-bit devices.