I had to go out last night in the snow to get a few grocery items, and I really wanted to try out theibotta and Checkout 51 apps.  There was a .50 coupon for a gallon of milk.
Before I go shopping, I always check the grocery sale ads in my area.  Since I live in a very remote area, there are only a few stores around.  After I plan my list, I take it to Walmart so I can price match.  I found milk on sale here:

...and I couldn't believe it!  This is the lowest price I've seen in a long while.  We usually buy 1% or 2%, but whole milk is a treat every once in a while, right?
I also bought Halls cough drops and price matched them at .99 and submitted it for a .50 through Checkout 51. Although I have to get up to $20.00 before I'll get a check and it might take several weeks, I think it's a great thing.  Have you tried the apps yet?