Hallfríður collaborated in the creation of the mouse Maximus Musicus to introduce children to classical music.
She received multiple awards and recognition for her work and was appointed Knight's Cross of the Icelandic Order of the Falcon in 2014.
Hallfríður received private tutoring in French music in Paris under Alain Marion between late 1991 and early 1992.
[4] Hallfríður was the Iceland Symphony Orchestra's leading flautist for more than two decades and performed in solo concerts with it.
[1] Hallfríður authored and served as artistic director in collaboration with the illustrator and violinist Þórarin Már Baldursson, the Iceland Symphony Orchestra, Ríkisútvarpið and Forlagið on an educational project concerning a mouse, which was called Maximus Musicus, to introduce children to classical music.
[8] In June 2020, Hallfríður received the honorary recognition from Garðabær "for an important contribution to culture and the arts".