Not really worth the effort. I've used this app for a long time now, but have barely earned anything back. Downloaded a different app and have already received more back than I ever did with Receipt Hog. Plus, I've never won anything substantial on the slot machine... pretty sure it's rigged. **Update (to response): Yes, I have been participating in those, which HAVE made it better, but I still stand by it taking so much longer than other apps to gain rewards.