I want to be able to use Scala to code iOS programs. Any tools available for this ?
Not today, but it may be close:
But, while Apple directly opposes the use of the JVM on iOS devices, it will make little sense to go that way (it's still early days). You will run into one obstacle after another, and won't have any guarantee that the code you write today, will run on the iOS of tomorrow.
Sit on the sideline with your Android, Ubuntu and popcorn, and let the big guys fight it out.
In the meantime.... you can write a thin front-end in PhoneGap (which works on most modern mobile devices), your services with Spray and have fun with your back-end in Scala.