Android App Notifications: Best Practices, Page 2
Making Each Android Notification Count
Notifications should be feature-rich. If at all possible, the notification should include all the information needed for the user to decide instantly whether or not to react now or later. This information should be as personal as possible. Take an email client notification for a new message. The app could just post a notification saying "You've got mail!", but this forces the user to launch the email app to find out more -- not a very personal message. The email application becomes much more useful when it includes some information in the notification, such as the message subject. This improved app creates a different notification that immediately gets the user's attention: "New email: Your house is on fire!"
Android notifications can be made personal and interesting in a number of ways, including by adding such things as identifying icons, titles, messages, and timestamps. Notifications can also include sound alerts, flash the LED light in certain colors and patterns, and vibrate the device. (See Figure 2 for a screenshot of a feature-rich Android notification.) When the user clicks on a notification, the underlying application launches to a screen where the use can find out more information related to the event that caused the notification.
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Figure 2. A Feature-Rich Android Notification
With all these options, it's easy to get carried away. Make your application notifications use these features for good, and not for evil. You're not trying to turn the device into a disco ball and you don't want your app to embarrass the user in a quiet meeting room.
Android Notifications for a Series of Events
Some of the notification examples previously listed require multiple steps. For example, a user might initiate a download on an Android app and when it's complete, the content will be available. It doesn't make sense to create separate notifications for each step of this process; this will just clutter the notification bar. Instead, the application can update an existing notification with the latest information as the previous information becomes outdated.
In other circumstances, you may want to keep all the history visible to the user. In that case, you should simply create a new notification with completely different data so the user knows more than one thing happened and that they aren't related. An email application may simply start to show the count of new messages in the same notification, however.
When to "Un-Notify" a User
Have you ever gone on vacation and returned to hundreds of emails, most of which no longer require your input because other coworkers dealt with them in your absence? Notifications are similar to those accumulated emails. Because they are time sensitive, many notifications have a rather short shelf life.
Luckily, your application can clear notifications as necessary, so consider doing so automatically when the usefulness of the notification has passed.
Notifications are most effective when they are used sparingly, for time sensitive events that the user needs to act on immediately. Know when to notify the user and when to have your application remain silent. Follow the best practices for Android notifications in this article, pack each notification with rich content that makes it worth reading and responding to, and if a notification's window of usefulness has closed, clear it to avoid cluttering the user's notification bar.