Polarity — Free download
Free
Free download; page says “Unlock for $14.99 USD” but does not specify billing term
Checked 11 Oct 2026
Plans and prices
jAMSKOOL pricing
Ear Trainer — Free
Free
Guess the Interval · Guess the Chord Quality · Sing Intervals
Checked 11 Oct 2026
Sing Trainer — Free
Free
All exercises at easy difficulty · Real-time pitch feedback · Voice calibration
Checked 11 Oct 2026
Build
$2.99, paid once
Two- and three-tone modes · Three difficulty levels · Soft and Hard modes · World leaderboard · Personal best tracking · All future updates
Checked 11 Oct 2026
kIDS
$4.99, paid once
All 7 quizzes · All difficulty levels · Party Mode · Random Notes mini-game · All future updates
Checked 11 Oct 2026
Sing Trainer — Unlock everything
$9.99, paid once
Medium and hard difficulty levels · Unlimited progress tracking · All future updates
Checked 11 Oct 2026
Ear Trainer — Unlock everything
$14.99, paid once
All remaining 9 quizzes · Party Mode · All difficulty levels and progress tracking · All future updates
Checked 11 Oct 2026