Can I test the add-in update process on a developer site

Question

I am trying to follow the add-in update process described in Update SharePoint Add-ins but on a developer site.

Where I got stuck is the point in the document that reads

Then upload the latest version of the add-in to your test site's add-in catalog and update every instance of the add-in.

As far as I can tell, the "Apps in Testing" document library is the add-in catalog on the developer site. However while I can upload a new version of the add-in package there, there seems to be no way of updating an already deployed instance of the add-in.

Namely, I just cannot complete this part of the instructions:

1. After the latest update is uploaded to the add-in catalog, open the Site Contents page on the website where the add-in is installed and choose the ... button on the add-in's tile.
2. On the callout that opens, choose the About tab. On the About page that opens, there is a notice that a new version is available.

As there simply is no About tab on the callout that's supposed to open in step #2 - only Details, Permissions, and Remove. Could it be because the add-in was initially deployed from Visual Studio and not by using the developer site's "New App to Deploy" function?

Answer 1

How to test a SharePoint app upgrade on an on-premises developer site:

• Publish the upgraded app package to a local folder and then upload it to the App Packages document library on the development sandbox. NOTE: It is recommended that you add a version number to the package file name so you then can easily recognize the appropriate package when performing an upgrade;
• Go to the Apps in Testing list by clicking on the list title on the development site's home page;
• Select the app to be upgraded (do not click on the app name as it would launch the app, just put a check mark next to the list item);
• Now in the ribbon above, click on the List tab;
• Click Upgrade an app
• In the popup appeared, choose the appropriate upgrade package you've uploaded on the first step and click OK