Naturally, users blame developers for their apps failing to deliver, but ultimately the manufacturer of your device has total control over the processes that run. Because smartphones are getting more and more powerful, and because battery capacity is lagging behind, manufacturers constantly try to put their own battery saving feature into the firmware with each new Android release. Many go so far that they break many apps just so they can try to squeeze a bit more juice out of the battery.
It's gotten so bad, there is a website devoted to these manufacturers and the hoops they make customers jump through just so they can find these default "battery saving" features and turn them off to get their apps to work. The site is called...
Don't Kill My App! https://dontkillmyapp.com/
If you go to this site, (which I recommend everyone do before they purchase their next phone or tablet), you will see that the worst offenders are (in order) Huawei, Samsung, OnePlus and Xiaomi. But by no means are these the only offenders.
Fortunately, the creators of this website have put together an extremely good list with pictures on how to get around these "battery saving" restrictions that manufacturers keep putting on their devices with every new Android update that comes out that cause apps to break and stop working.
So if you are having problems with the app not autostarting, or disappearing, or if the alarms don't work, check out this website to see if your manufacturer is on the list, and then follow the instructions under "Solution for users".
We test our apps on every new Android version that comes out, and when we get emails from users with problems, very often it is an issue with the extra "features" the manufacturer has added to their latest Android firmware update. Of course, we are more than happy to try to resolve any problem you might have by contacting us at the email addresses below, but the "Don't Kill My App! site is a great place to start to see if the manufacturer of your device and their new "battery saving" feature just might be the problem.
Don't Kill My App! https://dontkillmyapp.com/
bnbtfree@gmail.com
bnprobt@gmail.com