The makers of the game Below, has posted on there site saying how there game is going to be just timed exclusive.
Meaning it will be on Xbox One first, but after some time it will be available on other platforms.
Here is what they said
"Like many games on stage at E3, Below will be available on the Xbox One first. Then, after a period of time, CAPY can bring it elsewhere. It’s always been this way."
The full post is on there site.