Multifeed Google Shopping Feed

The only app on Shopify that can do what we need.
We tried 4 other apps before sticking with Woolytech. Setup was a little more difficult that expected, but the support staff bent over backwards to help us. There is a time zone delay, as they are Vietnam based, but they always respond within 24 hours. Ongoing support and Google troubleshooting has been invaluable. The app has all the features you might need, including: feed rules, feed formats, downloadability, auto-generated feed scheduling & API.