Here you can select iShala Global Scale to Tempered or Natural.
TEMPERED: A tempered scale is a musical tuning system that divides an octave into equal intervals. The most common tempered scale is the equal tempered scale, which is used to tune pianos and other instruments with a fixed scale.
NATURAL: This scale is based on ratios between tones that are derived from overtones. Notes are considered natural when they are not modified by a sharp or flat.