To customize how you get notified in 7shifts, you'll want to tap on 'Notification Settings' in the more menu.
From there, tap on the 'Notifications' tab at the bottom right of the screen.
To disable/enable a notification, simply tap on the 'message' or 'email' icons. If they appear in orange, it means they are enabled.
Push Notifications: If you have Push Notifications enabled, you will receive push notifications to your phone instead of text messages.