Vibrate Mode is an app to control your phone mode and quickly silence or put it in vibrate mode.
When you go into the app the device goes straight into vibrate mode, allowing you to adjust to any of the other modes afterward. As soon as you tap one of the available options, whether it's to keep or switch the current mode, the app then closes.
To be able to select the silent mode you'll need to grant that permission to Vibrate Mode, but it doesn't require any others, unlike Silent Mode Widget or vibrate mode by force.
Vibrate Mode lets you make these changes on your phone in a very fast and convenient way, especially if you let it create a shortcut on your home screen.