Since Becker-iGO does not have a back button from his own (all Becker devices have a hardware back button), should you not ask where you got the Becker-iGO from? Especially because the lower red one is mostly part of a Becker-iGO skin. The back buttons that are found with most downloads are square and situated at the top right corner (often (partly) blocking another button), like you see
h e r e in some of the screen shots.
I should add here that Becker skins are meant to use in a certain Becker-iGO release. When used in a different release, the skin won't fit the layout or something else may be wrong, meaning the skin won't function exactly as expected. There is no answer to give when that information is missing. Besides, I am no skinner.
FYI: some skins for Becker-iGO do have a close/exit button. Maybe that another skin (or release/skin combination) solves your question.