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What Key app for iPhone and iPad


4.6 ( 6336 ratings )
Music Education
Developer: Mark Carlotto
1.99 USD
Current version: 3.6, last update: 5 years ago
First release : 15 Jan 2009
App size: 4.16 Mb

What Key is a key detection app that determines the musical key of a song in real time. Using the pitch detection algorithm from Pitch to Note, What Key matches the notes being played to major, minor, blues, bebop (jazz) and other scales in all keys, picking the scale and key with the best match.

What Key is a universal app that runs on iPod Touch, iPhone, and iPad.

What Key works best on music with minimal percussion tuned to A4=440 Hz.

Pros and cons of What Key app for iPhone and iPad

What Key app good for

It seems to be a good program however I tested it on my Roland Juno g. Keyboard. And found it is a half step to high in its results. It is ok even great if you know that whatever results are shown is a half step to high and you adjust for it. I still give it four stars
I loved the old way that it just quickly displayed the major key. Now I see a bunch of graph lines and Im trying to read What Key by the jumping lines. Bummer.
Recent improvements have really made this tool very useful. Keep in mind that complex music often includes long segments which are essentially in a different key than the composition is written in. The author has done a very remarkable job with this app. My one suggestion is a display mode more suited to "upside down" portrait mode since the tendency is it point the phones microphone at the source. A remarkable app.

Some bad moments

Whenever I launched this application, the iPhone desktop appearance became striped. Even after I quit the application, the appearance of the menu would not return to normal until I restarted the iPhone. I regret paying anything for this app.
This app does not give the correct key or key signature of even the simplest notes. I also ran the app on the ipad and the iphone a the same time and they were both producing different results. Another free app that I already had and Logic both agreed with each other and they keyboard.
This app promises much more than it delivers. After trying it for awhile in both Live Music and iTunes mode, I could rarely get What Key to decide on which key any song was being played. Its a clever idea, but this app is just not ready for prime time.
This app isnt worth $2.39. Its a huge let down. I wish I could get a refund.
It likes to grab onto whatever chord is playing at the moment rather than listing for a period of time and determining the key. Itll lock in for a few seconds, some times.
Not happy with this at all. Wish Id not wasted my money on it