PS4
Sony is finally starting to allow cross-platform play between the PlayStation 4 and other platforms, namely the Xbox One. Granted, there is only one game that you can test at the moment but it's a start!

This update represents a major policy change for Sony. Even as recently as June, the company was actively blocking cross-play with other platforms, effectively making the PlayStation 4 a gaming island.

Fornite is the first game that Sony is testing to allow cross-platform play from the PlayStation 4 to platforms like the Xbox One, Android, iOS, Windows, iOS, and Switch.

John Kodera, the president and CEO of Sony Interactive Entertainment, shared the following on the PlayStation Blog earlier today.
Following a comprehensive evaluation process, SIE has identified a path toward supporting cross-platform features for select third party content. We recognize that PS4 players have been eagerly awaiting an update, and we appreciate the community’s continued patience as we have navigated through this issue to find a solution.

The first step will be an open beta beginning today for Fortnite that will allow for cross platform gameplay, progression and commerce across PlayStation 4, Android, iOS, Nintendo Switch, Xbox One, Microsoft Windows, and Mac operating systems. We see the beta as an opportunity to conduct thorough testing that ensures cross-platform play is best on PlayStation, while being mindful about the user experience from both a technical and social perspective.

For 24 years, we have strived to deliver the best gaming experience to our fans by providing a uniquely PlayStation perspective. Today, the communities around some games have evolved to the point where cross-platform experiences add significant value to players. In recognition of this, we have completed a thorough analysis of the business mechanics required to ensure that the PlayStation experience for our users remains intact today, and in the future, as we look to open up the platform.

This represents a major policy change for SIE, and we are now in the planning process across the organization to support this change. We will update the community once we have more details to share, including more specifics regarding the beta timeframe, and what this means for other titles going forward.

Now, the big question is: When will other games be allowed to join the party? Fans are still waiting for cross-play for games like Rocket League and Minecraft. I'm sure there's a good number of people that would also love to play games like the upcoming Call of Duty: Black Ops 4 together.