Amazing but filters and updated results need help – Karma | Shopping but better Review

This app is a life (and wallet!) saver. I've told all my friends about it. What prevents Shoptagr from being a five star app is the filtering. When I filter by "on sale" I also get low and out of stock results, defeating the whole purpose of filtering in the first place. I've also run into selecting and "on sale" item only to find out it's been out of stock (sometimes for months). This happens frequently.
Review by AlphieNumeric on Karma | Shopping but better.