I was really excited about this app but the "add app" button wouldn't work and it had to be installed via a link from customer support. Customer support is based in Australia and takes days to respond (even during Australian business hours.) After the app was added through the link from customer service, it still wasn't working correctly and wasn't displaying on my store. After waiting a couple days for a response from support, I ended up just deleting the app.
Thank you for your feedback - we are sorry to hear about the technical issues you are having. Our team had the Size App installed and working but it appears that the confirmation message to you was not received by your email service. We have been trying to get in touch with you to help resolve your issue. Please send us an email reply as we'd love to be able to get the Size Swatch displaying on your Shopify store.