Audiofile Engineering recently updated Quiztones, the ear training application for audio professionals and musicians, to version 1.5. Available as an app for iPhone, iPod touch, and iPad, Quiztones 1.5 sports a newly redesigned interface and a host of new features.

Quiztones is designed to train the ears to instantly and intuitively recognize frequencies. This is useful for tasks like mixing, adjusting EQ settings, and identifying and eliminating feedback.

Version 1.5 adds over 25 new frequency trainers, in the form of quizzes, in addition to the tones, pink noise, drums, acoustic guitar and vocal trainers originally included in version 1.0. Custom quizzes can also be made from songs in a user’s Music Library. New difficulty levels and scoring help the user keep track of their progress for the best results.

There is also a brand new in-app store for purchasing additional content. In addition to the original Quiz Pack of electric guitar & bass, version 1.5 adds two new Quiz Packs for in-app purchase: Strings 2 and Orchestra. New trainers will be coming soon to the Quiztones Store and can be added to expand the app even further.

Quiztones 1.5 requires iOS 4.2 or later on an iPhone, iPod touch, or iPad and is available through iTunes for $2.99.