1Password app for iOS is a widely used app/software for password(s) storage. Currently, it's impossible to type in the editor through the app (here, on xenforo.com). It doesn't even load the buttons, and it's impossible to change to the BB code editor. I guess it uses Safari as its core engine, but I'm not sure. Redactor's demo works fine.
Just to have an idea how popular it is:
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