Apple chose the 350 Swift Student Challenge winners from 37 countries and territories, then invited the 50 standouts, including Hoang, a final-year computer science student at Hanoi University of Science and Technology, to a three-day program at Apple Park in Cupertino during WWDC 2026, held June 8-12.
His winning app, HumMelody, records a melody as the user hums it and converts the sound into MIDI notes on screen in real time, which can then be played back on instruments such as guitar, piano, violin or flute.
"Many music lovers have good ideas but don't know how to express them, so I wanted to make an app that acts as a bridge, turning the ideas in their heads into something they can hear and feel," Hoang said.
The app uses a pitch-detection algorithm to read the hummed melody, and a visual editor lets users drag, delete or move individual notes before replaying the piece.
Hoang wrote it in Swift, the programming language Apple introduced in 2014, and built it entirely on Apple's own frameworks without third-party libraries. To work out how to edit notes after recording, he studied how professional tools such as GarageBand, Logic Pro and FL Studio handle the problem.
