I don't think any apps are up to date, which is exactly why this happened to you. Most of the data in such apps is years old, and it doesn't get updated in real time. Ultimately there is no substitution for learning to read labels. The following two lists are very helpful for anyone who is gluten sensitive and needs to avoid gluten when shopping. It's very important to learn to read labels and understand sources of hidden gluten, and to know some general information about product labelling--for example in the USA if wheat is a possible allergen it must be declared on a product's ingredient label like this: Allergens: Wheat.      

What is the best gluten free scanner app? I have the "gluten-free Scanner" app. I scanned an almond joy and it says it contains gluten when the package is labeled gluten free

Certainly, it would b wise to have a gene test done if your physician is open to it as it would provide some more data to understand what's going on. But keep in mind that the genetic test for celiac disease cannot be used as to diagnose celiac disease, only to establish the potential to develop active celiac disease. About 40% of the general population possess one or both of the primary genes known to be associated with the development of active celiac disease but only about 1% of the population actually develop active celiac disease. So, the gene test is an effective "rule out" tool but not an effective diagnostic tool.

Had Quaker gluten-free oatmeal last night and my stomach is a mess today. NO flu but def stomach stuff. Anyone else?

So you would be good with the diagnosis and not worry to check genetics etc etc? Appreciate your words!