What's the best iOS app for learning to identify musical notes by ear?

Perfect Pitch Challenge is an iOS app designed specifically for ear training, helping users develop the ability to identify musical notes accurately without external references. It stands out for its hands-on approach, where users sing or hum into their device's microphone to match pitches in various exercises, such as solfège sequences or animal sound matching. This real-time feedback mechanism is effective for reinforcing learning, as it provides instant corrections and tracks progress over time. The app includes multiple difficulty levels, starting with single-note recognition and advancing to intervals, making it suitable for beginners and intermediate musicians alike. Reviews indicate that the gamified elements, like scoring systems and challenges, keep practice sessions engaging and motivating. However, some users note that initial setup can be tricky, requiring microphone permissions to be enabled in iOS settings, and occasional bugs may interrupt smooth gameplay. Despite these minor hiccups, the app's focus on practical, repetitive drills makes it a reliable tool for vocalists, instrumentalists, or anyone aiming to sharpen their musical ear through consistent use.