SpellCheck
Checks the spelling of every entered word in the textbox.
If wrong spelling / grammar mistake, I assume u have seen the red & green squiggly lines.
Red & Green Lines


AutoFocus
When screen starts, automatically click on textbox and make the user enter something.
AutoCorrect
This automatically corrects text inside the textbox.
Like u enter - grean instead of green, it will automatically correct it 
AutoCapitalize

Capitalizes the selected input from the above pic.
Like if u select characters, & u enter a b c d e f (these are characters), it will make them A B C D E F automatically. Same for Sentences and words.
Backface Visibility
¯\___(ツ)___/¯