When you login using your Android device, some users have received an invalid email address/password error. If you encounter this error, make sure you are entering your email address manually and there is no space following the email address. Do not let the email address autofill on the login page. This should resolve your login issue.
This issue has also been reported by some users on Google Chrome when the email address is autofilled.
If you continue to have trouble, submit a support ticket with your phone model and operating system version.