This download is totally safe. AlarmApp.org is the developer of the app that can be found in the Communication category. On Google Play, AlarmApp is rated 3.7 by its users.
The latest release was on Mar 25, 2019 and this application was downloaded and installed by over 50K users. You can download the installation package of AlarmApp 1.8.1 free of charge and read users' reviews on Droid Informer. The app works fine on Android 4.3 and above.