Paid app ($0.99) — only Google Play can deliver it
Mute your phone with a single touch! Or keep it muted for a set time frame.
MuteIt! + — description
With a single touch, disable the ringtone and other sounds on your phone, and turn them back on again when you want! For the single touch feature, make sure to add the widget to your home screen.
You can also choose what time frame you want the phone to remain muted in from within the app itself.