“APFS, like HFS+, is case-sensitive on iOS and is available in case-sensitive and case-insensitive variants on macOS, with case-insensitive being the default. In macOS High Sierra, APFS is normalization-insensitive in both the case-insensitive and case-sensitive variants, using a hash-based native normalization scheme.Jul 10, 2017
Frequently Asked Questions - Apple Developer