Microsoft is soon going to drop support for the classic Windows Phone apps in a future release of Windows 10 Mobile. These classic Windows Phone apps, also known as Silverlight apps, will no longer work in the future version of Windows 10 Mobile. Microsoft has already removed support for Silverlight apps from internal builds of Windows 10 Mobile, where a warning is displayed when users try to open a Silverlight app that mentions “Silverlight apps are no longer supported on this version of Windows.”

It is very likely current Windows Phone devices will continue to be able to use Silverlight apps once this new version of Windows 10 Mobile is released, although that is yet to be confirmed.

A lot of the apps built for Windows Phone are Silverlight apps, even though they don’t get updated frequently. One of the most popular Silverlight apps is, of course, Facebook’s WhatsApp and Microsoft dropping support for Silverlight apps will effectively make WhatsApp unusable on the future version of Windows 10 Mobile unless Facebook releases a new Universal Windows Platform app for the service.

Dropping Silverlight support is technically a good thing for the future of Windows 10 on mobile devices, especially since Silverlight is quite old at this point of time. Microsoft would much rather invest in the Universal Windows Platform rather than wasting resources by supporting Silverlight. It is important to note that Microsoft dropping support for Silverlight apps is connected to do the latest reboot of its mobile business, so that’ll certainly be quite interesting to see.