...
It's always a good idea to clear out the cache, or browser history, and clear cookies on a regular basis.
Clearing from Google Chrome
See the link below for instructions on how to clear your browser cache in Google Chrome from your device.
...
http://www.refreshyourcache.com/en/firefox-20/
Clearing from Apple Safari
See the link below for instructions on how to clear your browser cache in Safari from your device. Remember to make sure that "Passwords" and "Autofill form data" are also checked off.
http://www.refreshyourcache.com/en/safari-5/