I am wanting to make an android app that will have user accounts. The app is like a contact manager and messaging app in one. Each contact will have a Name, a Number, and a password. Basically, the user will select from a spinner menu the contact name. The user will then enter the message. When the send button is clicked, the user will be asked to enter the password required to send to that specific number. The contact details will need to be kept private.
I have done some Google searches, however this is the closest i have come to finding anything: Android App : Managing user account information without a server
I am new to Android programing so any help would be much appreciated.
P.S. Sorry if this is somewhat vague