Piano Chord Judge

I know what the sound is, but I don't know what to call it a chord name!
I tried to make a song, but what is a chord?
It is an application that may be used in such cases.
Press the key on the piano to judge the chords. There is also a function to select a chord and check its constituent sound.
[Explanation of symbols for code judgment]
◎: Exact match.
○: There is a shortage of one sound.
△: Two sounds are insufficient.
×: Three lack of sound.
What? : There are insufficient 4 or more sounds, or there is extra sound
【Hold function】
You can hold down the key when you press the key. If you press the same key a second time, the key will be released.
All will be canceled with the Reset button.
【SelectChord function】
If you select a chord, you can check the constituent sound with the keyboard while producing the sound.
First pick the root tone, then choose Suffix such as minor or sus4.
【Inv function】
Judge the keys as Inversion chord.
【Others】
· If you transfer a MIDI file from iTunes, you can play that MIDI file with "Play" button. (You can stop with the Reset button)
· It is possible to connect to a MIDI keyboard compatible with Bluetooth.
· The keyboard can display up to 1 to 3 octaves.
· You can choose the tone colors, piano, marimba and bass so on.