Installing App Blocks in Your Theme
App Blocks (Theme App Extensions)
Some apps from the Cartly Marketplace can add UI elements directly into your storefront theme. These are called App Blocks. Once you install an app that supports App Blocks, you can place those blocks anywhere on your product pages, collection pages, or homepage ā without editing code.
What Can App Blocks Do?
Examples of what App Blocks can add to your storefront:
- Product review stars below the product title
- Loyalty points balance in the cart
- Upsell or cross-sell recommendations after the add-to-cart button
- Size guide popups tied to product metafields
- Live chat widgets in the page footer
Activating App Blocks
- Install the app from Apps ā App Marketplace. If the app supports App Blocks, a notification will confirm they are now available in your theme editor.
- Navigate to Online Store ā Themes and click Customize on your active theme.
- In the section panel on the left, scroll to the page type where you want to add the block (e.g., Product Pages).
- Click Add Section and look for the app's blocks under the Apps category.
- Drag the block to the desired position and configure its settings in the right panel.
- Click Save.
Configuring App Block Settings
Each App Block can have its own settings ā heading text, colors, visibility conditions. These appear in the editor's right panel when the block is selected, just like any other section settings.
Removing App Blocks
In the theme editor, select the App Block in the left panel and click the trash icon to remove it. Alternatively, uninstalling the app automatically removes all of its blocks from your theme templates.
Compatibility
App Blocks work with Liquid-based themes (Cartly 1.3+). If your theme was created before March 2026 and does not support App Blocks, reinstall or duplicate your theme to get the latest template structure.
Troubleshooting
- Block not appearing after install ā Make sure the app is fully installed and active. Try refreshing the theme editor.
- Block shows an error on storefront ā Contact the app developer. The block's render template may have an issue.
- Can't find the block in the editor ā Only Liquid themes support App Blocks. Switch to a compatible theme.