From the Store description:
MusicStation is a tool designed to find scales and chords through four search modes: By notes, by type, by root and by guitar position. It features no less than 63 scale types and 59 chord types!
Every discovered scale/chord can be played and shown either on a piano or a guitar. You can tune the guitar as you wish, with or without capo, no restriction is imposed. A Circle of Fifths, piano fingering sharts, an audio notepad, a chromatic tuner, and a metronome with sound, led and including tap, beat per measure and subdivision functions are also available.
If you're not sure what a 'Circle of Fifths' is (and I have to confess that this is on the limits of my own musical knowledge!) then you'll be fine with just the trial version - if you're a real muso and understand all the terms and modes here then the £5 or so purchase price will be insignificant compared to the other costs and expenses of your life, I suspect.
Here's a walkthrough of the main modes and functions in MusicStation:
The home screen is simple and obvious, just tap the function you need.....
The chromatic tuner is fast, colourful and works brilliantly. Job done, no other tuner needed - for me, at least.
Clearly falling into the 'labour of love' category, you can customise the colour scheme used throughout the application. Maybe to fit in with your band or orchestra's colours? Or to suit use at night?
The metronome is similarly useful, providing 'tap' mode, speed set according to number and also nudge controls. Not shown here in the screenshot (it proved elusive) is a flashing set of mock LEDs that count out the beat.
Now we're getting into the serious music territory - any key, any chord, any variant, can be sounded out and broken down (only the most common in the trial version, but that's fair enough).
Ah - the aforementioned circle of fifths - it's something to do with which sets of notes belong together in each scale variant - see here for full details on Wikipedia! I have to confess, I'm a little lost at this point!
As you'd expect, any chord can be displayed for guitarists or pianists in any inversion, with nudge controls...
There's also a bare-bones recording aid, in which you can record audio snippets and ideas - this works well in principle....
...though there's clearly work to be done in the retrieval and playback interface!
There's plenty of help text within the application too, though it does assume music knowledge from the user....
Plenty of settings too, letting you configure what happens as you move around the interface, plus setting up all sorts of alternative tuning systems...
Working through chords again, in the guitar fretboard view...
...and on the piano keyboard. The interface is at times confusing, but there's a lot of complexity under the hood here, so I'll cut the developer some slack...
After a few functions (per launch) you'll see this nag screen, but fair play to the developer, this is implemented is a very fair fashion and anyone you likes and needs the app will have no hesitation about buying.
Pretty comprehensive - a work in progress, but one which is worth installing and watching at the very least. You can grab MusicStation here in the Windows Phone Store.