You can use app extensions and embedded app libraries to extend the reach of your app and create seamless user experiences for merchants in Shopify.
App extensions let you extend your app's functionality into different areas of Shopify, including the Shopify admin, POS, Flow, and Online Store. By using app extensions for your apps, you can offer value directly to merchants within their workflows in Shopify.
By default, all newly created apps have the Embed in Shopify admin app extension enabled. This means that your app will load inside of Shopify admin. If you're building an embedded app, then you must use the Shopify App Bridge.
You can also use the Embed in Shopify POS app extension and the Shopify POS App SDK to embed your app within Shopify POS. With the Shopify POS App SDK, you can extend or add new features to Shopify POS for the iPad, iPhone, and Android devices.