At the moment, we do not support using Flowio app for all development stores, affiliate stores, partner test stores, or users who are still within the trial period of Shopify plans.
We're sorry for this inconvenience. But once you're in the paid Shopify plan officially, you could feel free to install Flowio app and enjoy all of its awesome features.
Hope this will be helpful for you.
Should you need further support, please feel free to contact us via live chat or email us at firstname.lastname@example.org