In Office 365, you can quickly and easily get to your email, calendars, documents, and apps using the Office 365 app launcher. These are apps you get with Office 365 as well as custom apps that you add from the SharePoint Store or Azure AD.
You can add your own custom tiles to the app launcher that point to:
SharePoint sites,
external sites,
legacy apps,
and more.
Let’s do it!
Access your Office 365 Portal: https://portal.office.com/ or https://www.office.com/
Click on “Admin” to access the Office 365 Admin Center.
In the Office 365 Admin Center you can search for: “company profile settings“
Or you can access “Settings – Organization profile“
Or access this link directly: https://portal.office.com/adminportal/home#/companyprofile
Scroll-down and find “Add custom tiles for your organization“
Click on “Edit“
Click on “Add a custom tile“
Fill out the required information:
Tile name: (I recommend a short name to avoid break lines)
URL: (it must be a valid URL that the user has access)
Description: (type something to help the user understand what is this tile about)
Image URL: (I recommend using icons with transparent background)
Click “Save“
After you have created all tiles you want you will see something like below:
Access your Office 365 Home
Click on the “waffle” or Office 365 app launcher
Select “NEW“
Done!
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You can also pin the new tiles to home.
Click on the “…” ellipses’
Select “Pin to home“
You have now your new tiles in your Office 365 home app launcher.
Hope you like it!
Reference: Add custom tiles to the app launcher – Office 365 Admin Help