[This corrects the article DOI: 10.2196/19225.].
©Helen V Jones, Harry Smith, Tim Cooksley, Philippa Jones, Toby Woolley, Derick Gwyn Murdoch, Dafydd Thomas, Betty Foster, Valerie Wakefield, Pasquale Innominato, Anna Mullard, Niladri Ghosal, Christian Subbe. Originally published in JMIR mHealth and uHealth (http://mhealth.jmir.org), 07.10.2020.