You can get the setup package of Veľký Grob 4.0.2 for free and check out users' reviews on Droid Informer. The app works fine on Android 4.0.3 and higher. This application is completely safe to download. Adsupra is the official developer of Veľký Grob which can be found in the Communication category.
The app has been downloaded and set up by over 100 users and the latest update is dated Aug 27, 2018. According to the latest info, this application is rated 5 on Google Play.