Indeed, when a device is opt-in to receive push notifications it should work on all android devices. However, there is a technical restriction you should be aware of.
The Standby Bucket
Since the Android 9 version (API level 28), and in order to improve device performance, a new battery management system called "Standby Buckets" has been implemented .
Standby Buckets help the device system to prioritize application resources based on usage frequency. Depending on usage patterns, the applications will be placed in different priority buckets.
The system has 5 priority buckets: Active, Working set, Frequent, Rare, and Never bucket.
Active: App is currently being used or was very recently used
Working set: App is in regular use
Frequent: App is often used, but not every day
Rare: App is not frequently used
In addition, there's a special "Never bucket" for apps that have been installed but have never been run. The system imposes severe restrictions on these apps.
By not using an application "Opt-in" to push notifications, the application will be degraded by the android OS and will have it added in the stand by app bucket.
This will cause some background processes in the phone to be refused. Example: "receiving push notification".
Targeting a number of devices that are "Opt-in" to push notifications, the campaign will be sent properly from FollowAnalytics (no error message), though push notifications will not be received.
Resource management mode for some Asian devices
On some android devices, we have observed some restrictions induced by "resource management modes" that aim to improve and optimize device performance.
Example: protected mode, battery management...
Some devices that "Opt-in" to receive push notification do not receive your campaigns. You will not see any error while sending the push from FollowAnalytics but the notification will not be displayed, as the device will prevent the notification display according to their resource management settings.
What should you do?
You can prevent this behavior by changing your device settings.
Go to protected mode to allow push notifications on apps that are automatically degraded.
Go to Settings on your Asian device
Tap Settings at the bottom of the screen
Select Special Access
Select Ignore Optimizations
Select doubleTwist (or CloudPlayer if you're using CloudPlayer) from the list and tap on Allow.
NOTE: The battery settings may be on a different menu on your specific phone model. If the above instructions don't work for you, you could try the following
Go to Phone Settings
Go to the Apps section
Select doubleTwist (or CloudPlayer if you're using CloudPlayer) and select App Info
Tap on Battery
Make sure the Power-intensive prompt option is disabled
On the same page, switch Launch from Automatic to Manage Manually
Enable all the Manage Manually options
If you have any further questions please do not hesitate to contact your CSM.
Thanks for reading !