The Update for Windows 10 players and Pocket Edition players to play together is live.
This is a guide for Local multiplayer:Both have to be on same Wifi connection and have the latest patch installed
Simply go into options on Minecraft and click on the option for 'Broadcast To LAN' then start your game. When the other player on another device starts up Minecraft, on their 'Worlds' selection it will show your world too, then they can simply join in and you can pass them diamonds.
I did this on my Windows 10 laptop while my partner did it on her iPad so it can be any Pocket Edition, not just the Pocket edition for older Windows devices or Windows Phone.
Hope this guide helpsI am a Pi Rho
has stated this can be done with the same account but on separate computers.
So if you have two computers or tablets then its possible to do without buying the game twice