Flight Board is an Android app that I use two ways. When I first start planning a trip I try to find a non-stop flight and Flight Board shows what current flights are coming in and from which cities. Looking at the left picture below, if I wanted a non-stop to Tampa, FL I have an option of flying out of Columbus, OH, arriving just before 2:00 pm. Touching that flight will display the airline and flight number on the right side of the picture. I like that every flight for every airline is listed unlike searching on most travel search engines which never include Southwest.
I also use the app during the day of travel to see if my flight is delayed and check if earlier flights are being delayed, indicating that might also happen to me.
Here's a link to the Android app.
The next link is to an iPhone/iPad app of the same name but by a different developer, it looks different but displays similar information.