Audital, now out on iOS, is tricky but ambient.
It's a concentric arcade game about managing the incoming traffic of circles and shapes. That's the hard bit.
While you do this, dynamically generated audio by Simon Hale, who won a BAFTA for his work on LA Noire, keeps you relatively chilled out.
Your goal is to safeguard a circle in the centre of the screen.
You do this by rotating a circular wall around that circle so that only the squares reach it. If one of the dark circles hits your big, central one then it reduces in size.
There are many nuances to this play. If a square hits your wall then you lose the chunk it hits, whereas circles bounce off it.
Sometimes, a square will cause another temporary wall to grow outside of your first one.
Audital is pretty, both visually and audibly, that's for sure. How long it will keep you entertained, I don't know, but its central conceit is at least challenging.
If you fancy giving it a go, it'll cost your £2.29 / $2.99 on the App Store.