©Xiaomeng Xu, Konstadina Griva, Mark Koh, Elaine Lum, Woan Shin Tan, Steven Thng, Josip Car. Originally published in JMIR mHealth and uHealth (http://mhealth.jmir.org), 29.10.2020.
This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in JMIR mHealth and uHealth, is properly cited. The complete bibliographic information, a link to the original publication on http://mhealth.jmir.org/, as well as this copyright and license information must be included.