The tool is completely secure for downloading. Widi Ariandi is the developer of this application that is related to the Productivity category. The app has the overall rating 4.6 on Google Play.
The developer rolled out a new version of the tool on Apr 23, 2019 and over 1M users downloaded and set up Kalender. Advertisements are a part of this application. It's free to get the installation package of Kalender, also, you can have a look at users' reviews on Droid Informer. The app works fine on Android 4.0.3 and higher.