If you want to set up your CSU email on your personal mobile device, a good place to start is the mail help page: http://help.mail.colostate.edu/o365splash.aspx

Here is the document for setting up CSU email on an Android phone: http://help.mail.colostate.edu/tt_o365_android.aspx 

Here is the document for setting up CSU email on an iPhone or iPad: http://help.mail.colostate.edu/tt_o365_iphone.aspx