Sale has ended but you can still get this app.
Download Time to Leave! Now

Official Description

Don't miss your upcoming appointments -- get notified on your device when you should leave to make it there on time! Takes into account your current location and traffic conditions along the way.

Sound familiar? "Google Now" used to provide this service until they either broke it, or discontinued it in late 2017.

NOTE: Because of the way Google charges for access to their directions API service, this app comes with NO embedded API key. You are required to sign up for and obtain a free Google API key, and are responsible for your own usage (typically pennies a month). Full instructions are provided within the app.