Is this product gluten free? Search tool online

There are many great lists of gluten free foods. I just stumbled onto Zeer this morning. It was helpful in locating the ingredients of a product I could not find online anywhere else!

I haven't checked it out to see how up to date the listing is, but I thought I'd pass it along in the event it may be helpful to someone else.
What is your favorite online or mobile app for referencing gluten free foods?