There are several differences between the classic API and the unified API:
The classic API does not support 64-bit applications.
Code exchange is cumbersome.
Binary reference:
Classic API: monutouch Unified API: Xamarin.iOS
Architecture:
Classic API: i386( for simulator), ARMV7 + ARMV7s + {ARMV&+ ARMV7s} for device Unified API: i386 , X86_64 , i386 + x86_64 (for simulator) + ARMV7 + ARMV7s + {ARMV&+ ARMV7s} + ARM64 + {ARMV7 + ARM64} + {ARMV7s + ARM64} + { ARMv7 + ARMv7s + ARm64} for device
Deployment target (default SDK version):
Classic API:7.0 Unified API: 8.0
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