Minecraft is all about creating 3D worlds, but sharing them outside of the game has always been a 2D experience -- you're sharing screenshots and videos like with any other game. Microsoft wants to do something better. It's releasing a beta version of its Better Together Update that, in addition to cross-platform play (more on that later), lets you export your creations in 3D. If you have Windows 10, you can use Paint 3D and Remix3D.com to showcase your work from every angle.
As for cross-platform support? The beta lets Android and Windows 10 fans play with other testers regardless of what devices they're using. Better Together also establishes a more common feature set, including in-game objects like fireworks and stained glass. You'll need to meet some basic conditions to check out the beta (install the Xbox Insider app on Windows 10, or own a Google Play copy of Minecraft on Android), but you're otherwise free to try the new features right away.