Reviews.io integrates with Opencart version 3. Users can install the Reviews.io Product Review plugin quite simply using the Opencart dashboard.
Download Reviews.io plugin file
Download the Reviews.io Opencart Product Review Plugin
Save the file reviews.co.uk.ocmod.zip somewhere convenient, you'll need it shortly.
Log in to your Opencart Administration Interface
Navigate to Extensions >> Installer
Click Upload and choose the reviews.co.uk.ocmod.zip to upload
When complete you'll see the extension in your Install History at the bottom of the screen
Navigate to Extensions on the left menu. This displays a list of currently installed extensions
Scroll down to the Reviews.io Product Widget extension
Add your Reviews API key and Store Key
Click the blue pen-shaped Edit button
Navigate to Extensions >> Modifications
Click the blue Refresh symbol in the top right bank of icons (it's the leftmost one)
Adding the widget to your product page
Navigate to Design >> Layouts >> Product
Using the Opencart Product Page Interface, select the page location that you wish to add the Reviews.io Product Widget. In the example below, we have chosen to install it in the Content Bottom section of the theme.
Important: If you're using custom templates in OpenCart then custom modifications to the plugin will be required