FAQ about Library and Dependency Apps in Business Central

Article
05/11/2023

This section contains answers to frequently asked questions about library apps and dependency apps in Business Central.

What is a library app?

A library app contains common code that other apps depend on. If you're going to have multiple AppSource apps that all share common code, such as licensing, registration, and so on, you can put that common code into a library app and have the AppSource apps depend on the library app.

How does the library app get installed to a tenant?

A library app doesn't appear on AppSource. It only lives in Business Central. Our service is built to install the library apps behind the scenes. Here's how it works. Customers find an app they want to install on AppSource. That customer doesn't know the app even has library app(s). When they select to install the app, our service looks into that apps json/manifest to see if it first needs to install any library/dependency apps it may depend on. If so, it installs them first before installing the main AppSource app.

What is a dependency app?

A dependency app isn’t much different from a library app. A dependency app does have its own offer on AppSource. For example, you might have AppSource “App A” that serves a purpose on its own and is listed on AppSource. You then also have “App B” as its own offer on AppSource but it does depend on code within “App A” and needs “App A” to be installed before it can be installed. This is really the only difference though. Behind the scenes, library and dependency apps behave the same when it comes to walking that dependency chain and auto installing any app the top-level app depends on.

Can I have multiple library apps for my AppSource app?

Yes. Just make sure you list all library apps as dependencies within the AppSource app json file/manifest.

When I get the latest updated version of my app, why don't I get the updated library/dependency apps that my AppSource app depends on?

Libraries are updated only when the new version of your app requires a higher version than the version currently installed in your environment. If you want your library app to be automatically updated when your AppSource app is updated, you must increase the minimum version required in the manifest (app.json) of your AppSource app.

You can also uninstall and reinstall the library/dependency app to have it updated.

What are the validation requirements for library apps

Library apps only get validated technically, but don't go through any type of marketing validation. The technical requirements are described here.