Table of Contents
App persistence and notifications on the Kyocera DIGNO Keitai 4
Due to the device only having 1 GB of RAM, apps are regularly killed in the background. There are also multiple issues with receiving notifications due to the lack of Firebase Cloud Messaging (FCM).
Fixing notifications
FCM is a part of Google Play Services, which typically handles notifications in an efficient manner. FCM allows apps to remain inactive, and to be woken up by the service when notification is received. This can be mitigated by rooting the phone and using microG to reinstate FCM.
Systemizer may be used to keep apps alive and sending notifications, but may cause additional battery drain.
In the context of SMS, any SMS app other than the stock messaging app or Google Messages will have messages deleted when closed due to a device specific issue. This can be solved by systemizing the app.
Using microG to reinstate FCM
See Using microG for setting up microG and enabling FCM.
Systemizing apps to keep them alive
See the Systemizer page for information on the process of systemizing.
Third-party SMS apps
The DIGNO 4 seems to have a device specific issue where third-party texting apps are not whitelisted, which causes them to not receive texts while closed. Systemizing a third-party texting app such as QUIK to Apps will fix this behavior.