Using Apps with themes
Visit Shopify's help centre for an extensive guide on extending your theme with apps.
Online Store 2.0 and compatible themes
The majority of Shopify Apps are developed by third-party developers. Before committing to an app, it can be worthwhile reviewing the app documentation or contacting their support for information on how it integrates into themes.
As theme developers, we're unable to modify our code to make our themes compatible with any app because resolving one issue for one app often introduces errors in other theme functionality or other apps. Instead, we do offer app developers access to our code so they can make the necessary changes on their end to make their app work with our themes.
Apps and performance
Updating themes with apps
Adding apps to your store can help add new features and functionality, but can often make theme maintenance a little more complex.
Depending on the theme version you're running, some apps may require custom code to be added to theme template files. When updating your theme, these customizations will have to be added back in to the new version.