This app was mentioned in 1 comment, with an average of 1.00 upvote
Something like these, but updated
https://play.google.com/store/apps/details?id=by.karneichik.simplepricecompare
https://play.google.com/store/apps/details?id=leoliang.unitpricecompare
This one looks decent https://play.google.com/store/apps/details?id=ca.brainservice.pricecruncher.free