To uninstall/install the application from scratch:

It's highly recommended that you clear the apps' cache and data prior to uninstalling the app as explained here. Afterwards, tap on the settings of your device > Select Apps (Application Manager) > All > tap on Hotspot Shield > tap on Uninstall.

NOTE: In some cases, you may find that the "Uninstall"  is greyed out.

Sometimes some applications have more privileges than a normal app would have. Therefore you will need to delete Hotspot Shield from your Android device:

1. Go to the General Settings of your device and look for Security.
2. Tap on Phone Administrator (on some devices, this is called Device Administrators)
3. Uncheck Hotspot Shield
4. The Uninstall button will now be enabled and Hotspot Shield can be uninstalled as explained above.

Installing Hotspot Shield:

1. On your Android, launch Google Play > Search for Hotspot Shield 
2. Tap the Hotspot Shield app and tap Install 
3. Then tap Accept for the Terms and Conditions and launch Hotspot Shield
4. Tap Next and select the checkbox for "I trust this application" and then tap OK.