Today I came across this very well-done Z80 Reference app for iOS. It's totally free and seems like it will be really handy. Check it out if you've got an iPhone or an iPad.
https://apps.apple.com/ca/app/z80-refer ... 1453302679
Z80 Reference app [iOS]
Re: Z80 Reference app [iOS]
Looks much nicer than what's available for Android. Unfortunately I don't own any Apple products (well except for an Apple 2e 
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