When I login to PA control panel using iOS (e.g. iPad) the first letter of the login is automatically capitalized. The same happens with the domain name when registering the domain from CCP and with some other fields of CCP.
Autocapitalize attribute is not set for the fields, therefore the browser chooses whether or not to use automatic capitalization. There is a feature request with id #POA-87459 to disable autocapitalization where necessary.