Password protection of spreadsheet
I just posted this question to Microsoft forums and found out that this feature is still not functional in Excel for iOS:
I'm using Excel on an iPad Pro and would just tried to find a way to password protect a spreadsheet I'm saving to OneDrive. Searching the general web and these forums didn't readily surface an answer. I've seen old responses indicating that it wasn't possible to password protect a single sheet in 2014; however, I'd be surprised if it's not even possible to password protect an entire spreadsheet in the latest version of Excel for iOS.
Use Numbers or a 3rd party Office until this issue is resolved. Not being able to protect sensitive info in 2018 is unacceptable, given all the hacking / data breaches going around.
Eduardo Santos commented
Incredible that this does not exist. Incredible that we are shoved to User Forums where venting is the only recourse.