Both the Android and iOS app require the same information when logging in to the app. In order to log in, you must have first created your Datto Drive account at dattodrive.com.
Once launched, the app will display a login screen as below.
The Server address is the subdomain you created when you were registering for your account. It will be in the form <subdomain>.dattodrive.com.
The Username is the email address you used to create your Datto Drive account.
The Password is also the same password you used when registering.