Yes, there's no recompiling that can be done anyway if you only have the binary and no source code. Writing the new machine code would overwrite some code at the start of the function you're modifying, but that doesn't matter if you just want the function to return true or false.
You could edit the binary manually with a hex editor, but some disassemblers like Hopper have a feature where you can type new instructions in assembly and it will assemble and insert them for you. I'm sure IDA pro has something like that as well.
It would be incredibly cool to have a script that automatically manages your inventory while playing the game, e.g. the player picks up all items and has the script auto-drop them if they don't meet certain requirements (value/weight ratio, duplicates, etc.). I'm excited to see where this goes!
That's the default header created by Xcode when making a new file, I didn't add that on purpose. I suppose I should go through and get rid of those lines.
This is somewhat anecdotal but with the latest iOS and Facebook app versions, Facebook doesn't even show up on the list of apps that have requested to use my microphone. Unless they found some exploit to bypass Apple's restrictions and use my microphone without even asking for permission, I seriously doubt they're listening to users.
None of the things you mentioned are possible without jailbreaking, but I think workflow's creators are planning to bring extra features like those to it through a jailbroken plugin of some kind.
Maybe I'm misinterpreting but I assumed the subreddit would be a collection of answers like this instead of a place to ask them which would be super cool and helpful. Not sure if that's what's meant though.
You could edit the binary manually with a hex editor, but some disassemblers like Hopper have a feature where you can type new instructions in assembly and it will assemble and insert them for you. I'm sure IDA pro has something like that as well.