Having acquired an Ant+ speed/cadence sensor recently I started looking into options for using it to calculate power when I'm on my Turbo. The best option appeared to be Trainer Road, but it requires a PC with an Ant+ USB stick to work. As I do my training in my garage, there was no convenient place to put a laptop and I also didn't want to fork out £30 on a usb stick.
I own a Samsung Galaxy S4 which has Ant+ built in (as do many other smartphones) so I decided to write an app to do the basic functionality provided by Trainer Road and release it completely free of charge (no upfront cost and no adverts!) for others who might find it useful.
It's called Turbo Power Free and it's on the Android store now if it's of any interest to you.