Another weird SharePoint app bug happened yesterday. The solution was fairly easy once you know what's going on, but it's just weird altogether.
You have a custom app in your SharePoint 2013 App Catalog.
[ ](https://www.edinkapic.com/wp-content/uploads/2015/03/appcatalog1.jpg) A Custom App Inside App Catalog[/caption]
You want to add this app to a SharePoint site. You can't find your app in the "From Your Organization" section when you click at "Add an app" in a site.
[ ](https://www.edinkapic.com/wp-content/uploads/2015/03/appsYouCanAdd1.jpg) The App Is Missing From "Your Apps"[/caption]
I first suspected that the current user doesn't have permissions to add an app. However, the user is the site collection administration and thus has the permission to install an app.
Yet...a slight detail. The App Catalog site is, well, a SharePoint site. With its own permissions. And, by default, containing only the user who created the catalog in the first place (the system admin).
So, the current user, although a site collection admin, doesn't have permissions to read from the app catalog. (This is the weird part, as I expected SharePoint to do the reading using a system account behind the scenes.)
Add the users that should be able to install your custom apps to the site permissions of the App Catalog site, with Read permission level. In my case it was "Dani Alves" (yes, I'm a Barcelona fan).
Now, the app is visible in "Your Apps" when you try to add it to a site. Yeah