Currently the Zapmap app does not allow users to directly change their own email but we are busy working on this function and expect this feature to be released in the future.
In the meantime, simply contact our support team who will be able to change over your email address very quickly for you. This allows you to retain your charging history and you don't end up with 2 accounts. If you have a charging card and/or Zapmap charging credit, this also ensures that these elements are retained for you.