Notifications on Android Platform

Notifications allow displaying information outside of the normal UI of an app. Any notification first appears as an app icon in the notifications area. The details of a notification can be viewed by the user by opening the notification drawer. The notification area and notification drawer are system controlled and can be viewed by the user any time they want to.

Notification icons in the notification area.

Notifications in the notification drawer

Notification on the lock screen.

Starting from API level 26, running Android 8.0 and higher, and on supported launchers:

• Notification badges can be displayed by apps on app icons.
• Long pressing app icons can give the users a glance at the notifications that have been associated with the notification badge.

Notification badges being displayed by apps on app icons.

Long pressing an app icon reveals the notifications related to the notification badge.

The function of a notification

Notifications are a means to provide short, timely, and relevant information about the app even when it is not in use. Introduction of notification can increase app engagement and keep the user connected to an app while also providing extra value and hopefully increase user retention.

The most effective types of notifications are:

• Communication from other users
• Well-timed and informative task reminders for the user

Components of a notification

The anatomy of a notification consists of the following components:

• Header area
  • app icon
  • app name
  • header text (optional)
  • timestamp (optional)
  • expand indicator
• Content area
  • the content title
  • and the content text
  • also a large icon (optional)
• Action area
  • Can accommodate up to three actions, but icon also needs to be provided for backward compatibility.

Types of Notification

There are two types of notification:

• Transactional notifications
  • Enable human-to-human interaction
  • Function better in daily life
  • Control or resolve transient device states
• Non-transactional
  • If notifications don’t fall into the above category they are non-transactional
  • Two approaches for non-transactional notification (opt-out and opt-in)