Another clever way which can be used in older versions of android and can be used anywhere in string so it's handier even in latest version of android, is to include the right-to-left mark or even left-to-right mark in the string when it's needed:
left-to-right mark: ‎ or ‎ (U+200E)
right-to-left mark: ‏ or ‏ (U+200F)
This is how it's down:
String rtl = "Hello u200F(????)";
The good thing about this method is you can even use it after punctuation like (,{,[,! which are positioned right incorrectly! examples:
????! // wrong position
????!? // right position by adding RLM after !
look how ! is positioned correctly in second line, actually there is an RLM after it, and you can copy paste it even if it's invisible.
The second good thing as you saw it is that you can use this method (these char codes) in any system that supports RTL like browsers, word and so on.
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