Sentinel Hub
Web address: https://www.sentinel-hub.com/
This is a very useful site for generating real time and historical maps base on images from a complete archive of Sentinel-1, Sentinel-2, Sentinel-3, archives of Landsat 5,7 and 8, Envisat, Merit, Proba-V and GIBS products; All open source and free to use. Various layers are available. Information for drought management such as soil moisture, NDVI, PASG, VCI and water status are daily updated. Subscription at a very reasonable price is available for commercial use.