Proxy Toggle (NoRoot) Free

Protect your browsing privacy, hide your location, and bypass site blocks.

Pro version (no ads):
https://play.google.com/store/apps/details?id=com.givenocode.proxytoggle.pro

You will be able to turn on/off proxy by one click from App, Widget, ActionBar or from anywhere else with floating widget.
All your proxy settings are stored and you can switch between them quickly
Bypass management via Proxy Toggle is very handy.
Also App monitors WiFi state and updates it's data regarding to it. (You can turn off this function)