A minor pentatonic scale
A C D E G
Formula: 1 ♭3 4 5 ♭7
Natural minor without its 2nd and 6th. The guitar's most played scale, and usually the first one a guitarist learns.
On the neck, frets 0 to 12
The 1st string (high e) is at the top, as in the app. The root is filled.
Open it in the app: 3. Scales & Modes, in A
The minor pentatonic scale in other keys