How to notify users about an Android app update?

I've built an Android app which is now on Play Market. From time to time, I make updates to it, and I'd like to let users know that a new version is available.

How can I send an update notification to the users of the app?

You do not need to do anything specific for this. Since you mentioned that you are using Google Play, the update notification is taken care of by Google Play.

You just need to update the APK with a higher versionCode and Google Play should do the rest.

You can do this in a lot of ways, depending on when you want the user to be able to see that there is an update available.

If you want the user to know about the update when the app is started, just create a utility method (inside the onCreate method of your main/first Activity) that checks if a newer version is available in Google Play. If it does, display an alert dialog with a relevant message and an Intent which opens your app in Google Play when the user clicks on the positive button of the alert dialog. If you are updating the app regularly, the user will keep getting this alert dialog every time the app is started and hence, may get irritated. Thus, this is not the best approach.

If you want the user to get a notification on the phone (and not when the user starts the app), you can use the AlarmManager class to schedule a background service which checks for an update at regular intervals. If the service finds that an upgrade is actually available, publish a notification with an intent that opens your app in Google Play.

Of course, another approach is to leave it to the OS itself. If the user has not set the "Automatically update" preference for your app, the user will get a notification regularly about an update available for your, as well as any other apps. But not all users enable background data on their devices, so this is not completely reliable.

In the end, you must respect the users preferences. If the user does not want to automatically update the app, or does not want to see a nagging dialog box whenever he/she starts your app, don't alert the user about the update.

In my opinion, you should create a PreferenceActivity that has a preference like "Check for updates regularly", which can be set from within your app. If it is set, do the needful in your own service. May be even give the user an option to select the period after which the service will check for an update.

I hope this helps!

It is up to each phone owner if she wants to be notified on new versions by google play, and it's up to each phone's manufacturer if this is to be enabled by default.

If you however are in a situation where you "require" the user to update to the new version to be compatible with some form of protocol or you have a similar similar use case where you have a server component somewhere, you might want to notify the user of a potential version conflict in the UI based on information about what is the latest version.

This information can be grabbed directrly from google play, however as @Yahel pointed out in this question google play is a closed system with no official API, and you might need to rely on unpredictable undocumented API. There is an unofficial API library here.

This leaves only one option, which is to keep this information on your own server. If you allready have a serverside this might be trivial. Simply put the latest version in an XML file and retreive that at regular intervals from your code. If the version code is outdated, trigger the notification in your UI. Here is an example implementation for doing that.

I hope this was helpful :-)