The DG Piano Chords Android application is very easy to use.
The screen is divided into 4 regions, as shown in the following figure:
There are four regions: 3 button grids, and one central graphics frame:
When you are operating the application, all you have to do is to choose one button from each of these button grids.
Immediately after, the chosen chord is displayed on the central frame, the yellow area on the figure shown above.
The central frame displays the chosen chord graphically, and also by name (on the bottom).
When you tap on the fretboard, it switches between displaying the notes of the chord pattern, or the intervals.
The intervals are particularly important for a musician, because it will help you identify where the root is, and its relationship to the other notes in the chord. Also, by studying the intervals, you come to understand the logic behind the chords, and you will be able to deduce them yourself.
Pressing the R, 1, or 2 buttons will show you the main inversions;
additionally, pressing the ">>" or "<<" buttons will take you to the next or previous inversion.
Standard triads ( such as "M", "m", "aug", "dim", sus4"), have only 3 inversions (root position, plus 1st, and, 2nd inversion).
Quadruple chords (such as 7ths, and 6ths) have 4 inversions; 9th chords have 5 inversions.
The keyboard shows 2 octaves which is sufficient to show you the main chords and inversions.
The circles in pink color represent the possible finger positions. In practice, some musicians split the notes between two hands, or drop some of the notes all together.
For example, on a 7th chord, you may drop the 5th. On a 9th chord, you may drop the 3rd, or the root (if you are playing in a band and there is a bassist).
This application is ideal to help you explore and learn the chords to play with a "fake" book.
Feel free to explore and discover which inversions make your song's chord progressions easier.
If you are a newbie, we suggest you learn all the major (M), minor (m), and 7th chords first, in all their inversions. Next, learn the 6ths, diminished, and augmented. This covers 80% of the music available, and then gradually, you may learn the most sophisticated chords 9ths, sus4, etc, as you need them.