According to Microsoft Best Practices, you should use Add-ins (previously known as apps) when customizing your SharePoint 2016 deployment. Furthermore, plenty of third-party vendors offer Add-ins in the SharePoint Store, which is similar to Apple iTunes or Google Play, but for SharePoint.
However, compared to your smartphone, you need more than an Internet connection to install Add-ins in SharePoint. Being able to consume Add-ins in SharePoint requires some configuration not only in SharePoint, but in ...