During a crisis, the messaging platform WhatsApp allows crisis-related information to be disseminated quickly. Although case studies have documented how WhatsApp has shaped crisis outcomes in both beneficial and harmful ways, little is known about: (i) how crisis-related content is spread; (ii) characteristics of users based on usage patterns; or (iii) how usage patterns link to well-being. During the coronavirus disease 2019 (COVID-19) crisis, this study used the experience sampling method to track the daily WhatsApp usage of 151 adults throughout one week (capturing a total of 924 days of crisis-related communication). Each day, participants reported the extent to which they had received, forwarded, or discussed COVID-19- related content. During the week-long monitoring, most participants (94.7%) reported at least one COVID-19 related use of WhatsApp. Those who engaged with more COVID-19 content in personal chats were more likely to report having COVID-19 thoughts throughout the day. We further observed that around 1 in 10 individuals (14%) were chronic users who received and shared forwarded COVID-19 messages at a high volume; this group may represent everyday "super spreaders" of crisis-related content. Together, these findings provide an empirical base for policy makers to manage risk communication during large-scale crises.