iPhone and iPad apps tagged "Esperanto."
Votara to traduki Angla en Esperanto Aplikajo
Sofweb's Esperanto is a votara to traduki Angla en Esperanto. (Softweb's Esperanto is a dictionary to translate English into Esperanto.)
You already knew that, I'll bet. That's what Esperanto is all about: It's a universal second language that is supposed to be easy to learn and understood by everyone.