Adapting an Evidence-Based e-Learning Cognitive Behavioral Therapy Program Into a Mobile App for People Experiencing Gambling-Related Problems: Formative Study oleh Gayl Humphrey, Joanna Ting Chu, Rebecca Ruwhiu-Collins, Stephanie Erick-Peleti, Nicki Dowling, Stephanie Merkouris, David Newcombe, Simone Rodda, Elsie Ho, Vili Nosa, Varsha Parag, Christopher Bullen