AR: Buy GTINs/UPC/EAN barcodes

The reviews for the AR: Buy GTIN/UPC barcodes Shopify App are overwhelmingly positive, highlighting its ease of use, effectiveness in adding GTINs to products, and excellent customer support. Users appreciate the app's ability to quickly resolve issues with Google Merchant Center, improve Google Shopping performance, and save time in managing product listings. The one-time purchase model without subscription fees is praised for being cost-effective. However, there are a few mentions of the app being slightly expensive for some users.