GeoGebra web application can be used with any device running Internet Explorer 11 or recent versions of Google Chrome, Safari, Mozilla Firefox or Edge. It is available documentation about Tablet App.
See Reference:GeoGebra Installation for details.
GeoGebra Apps require iOS 9.3 or above
The GeoGebra Apps are available for Android 4.4, but Android 5.0 or later is recommended for full exam-mode support.