The Covid Inquiry has revealed how the use of chat apps in government created an unprecedented document trail, along with a temptation to avoid record keeping or to lose/delete records. Ben Worthy (of Birkbeck College) and I have co-authored a piece about this for Political Quarterly – https://politicalquarterly.org.uk/blog/government-by-whatsapp-covid-transparency-and-government-by-text/ .