After three weeks of utilizing this app. I can safely say that on my A1P ZTE USA Axon by ZTE the app actually does somewhat of what it claims that shutting down background apps will save battery life and decrease heating. I was experiencing overheating on the phone and some lag. As you can see from the video below I do have multiple apps that I utilize on a daily basis. I purposely opened and allowed to run a few minutes for the video to show how it functions. From my recording, the app shuts down about 9 background applications that are draining battery and bandwidth. After they were shut down the you could tell that the phone's temperature was coming down so I opened CPU-Z to show the results of the process I had engaged.
CPU-Z clearly showed a drop in CPU processes while the thermal displayed the phones over all cooling. I previously went ahead and opened Cooler Master to display the real time cooling. Although I understand that the Cooler Master application can be misleading, for the purposes of this video, I wanted to show that it does cool and that the previous background apps were no longer activated. Which they were not but other background apps started. Also yes running antivirus on Android is not necessary but I do transfer apps and files sporadically.
Shut App has a few features that include a white-list to ensure the apps that you really need, to stay activated. it has a magic ball which is a widget that activates when an app is sitting in the background consuming battery and bandwidth. Which I showcased in the start of the video. It has a PocketShut feature where once activated , apps will be auto closed with phone in your pocket. $4.99 for that feature to be enabled or you can invite three friends to use the app and hopefully buy. I do like the feature that it contains a link to Doze, for those that do not have Marshmallow as of yet and wish to utilize it. Android 6.0 has it built in which this phone has. It is a no frills application but as I commented previously it does as it claims somewhat on this phone, on another it performed excellently and there is improvement on performance. For this phone though I believe there is contraindication as the antivirus as a built in cleaner as well from what you saw in the video.
I do utilize it and recommend a spin with it to learn if it fits your needs. Of course as with any recommendation I do have to express a disclaimer that individual experience may vary. I hope you find this informative and I thank you for taking the time to read and view.
Video of in action: