The main platforms that currently, support cross-platform play are Xbox One, PS4, Nintendo Switch, Windows 10, iOS and Android.
Guest accounts can only be signed in at the start of a session; they can not join existing sessions.
"Your Xbox Live settings do not allow multiplayer games. This includes Minecraft on mobile phones, PS4, Xbox One, Nintendo Switch, and Minecraft: Windows 10 Edition. I did this. A Microsoft account isn't necessarily needed to play Minecraft. A look inside the game. Check your privacy and online safety settings on Xbox.com to make sure you have Xbox Live Gold and that your settings allow multiplayer."
*Owners of a digital version of Minecraft: Xbox One Edition can download the new, updated game in the Microsoft Store for free.
Available as a physical disc or digitally from the Xbox store. We’re launching a Multiplayer All-Access event with a free unlock of Minecraft: Xbox One Edition.Xbox is inviting all Xbox Live members, with or without a Gold membership, to play online with friends for free in any game they own during our Multiplayer All-Access event from May 18-21 on Xbox One and Xbox 360. You cannot use a mobile phone to play Minecraft with someone who is playing Minecraft: Java Edition on PC. In turn, have the secondary player join the now open LAN game. You should see, more or less, exactly what we see in the screenshot above: the secondary player with the new username and the default Steve skin. Per the Minecraft Wiki: On Xbox, Local Splitscreen can be played using Local, Silver and Gold accounts, while Online Splitscreen can only be played using Gold and Guest accounts. Until January 30th, 2018, owners of the disc version of Minecraft: Xbox One Edition can download the new game once they have played Minecraft for 5 or more hours in the past 12 months OR purchased a DLC Pack. You can play local splitscreen only without Xbox Live. To test things out go ahead and fire up a Minecraft game on the primary computer, load a map, and open the map for LAN play. Minecraft on Xbox 360 supports split-screen play for up to four players, and offers specially crafted skin-packs, console-only competitive modes, mini games and more!
This allows you to play Minecraft with other people in your household.
In September 2017, we released the Better Together update for Minecraft on Xbox One, iOS, Android, the Windows 10 version and Gear VR (and since then, we’ve added Nintendo Switch to the Better Together family).
This update was essentially a new version of the game, the Bedrock version, which let Minecraft players enjoy multiplayer with each other across all those platforms! I have everything allowed and I can play any other game online with no issues.