Tabletárium is completely secure for downloading. The tool has been originally created by SCIENCE IN and it is related to the Educational category. The latest release was on Jun 30, 2015 and this application was downloaded and installed by over 100 users.
It's free to get the installer of Tabletárium, also, you can have a look at users' reviews on Droid Informer. The app runs on Android 4.0 and above.