Basically, Hotspot Shield creates a virtual private network (VPN) between your Android device and your Internet provider. It's thanks to the VPN that you will be protected against snoopers, hackers, ISPs, and any suspicious activity that goes against your privacy and security. And, it's also useful for accessing those sites that normally have region-blocked content.
The program doesn't need any complicated configuration, nor does it have dozens of options to trip you up. Just run it, it will alert you that your connection is protected, and you're good to go. It's as easy as it is effective.
Hotspot Shield VPN is a useful tool for users that like to keep their browsing private, or that want to access websites that are normally geographically restricted.