This app required me to manually enter every item in my stores individual URL's one at a time from my suppliers in order to track the product. This does not work for me seeing as how i have over 2000 products. They did offer me a refund though so i gave them an extra star.
Sorry about your bad experience, inventorify won't recognize your supplier if the SKU field in Shopify is empty. In such case, you'll be asked to enter the product URL manually, Else, if you are using a lister which imports the source site SKU you'll be able to add the product to the monitor easily.