The developer rolled out a new version of this application on Nov 11, 2019 and over 1M users downloaded and installed Battery Saver Frank-remark. Advertisements are a part of the app. A free .apk installation package of Battery Saver Frank-remark 1.0.16 can be downloaded from Droid Informer and you can have a look at users' reviews on this site. Prepare 25 MB of free space on your device for this app installer and keep in mind that it works fine on Android 5.0 and higher.
As users state, you can experience the strong points of the app that are a simple interface, useful features and battery saving mode. In users’ view, you can notice such a drawback of this application as too many ads.