Per User:Nick_Moyes and @TheDJ at https://www.mediawiki.org/wiki/Topic:V6nknm0p8uc8mtao people who read Wikipedia articles on their mobile devices are unable to sort tables, even when the tables are marked as sortable in the wikitext.
T181452: Add sortability to tables with "sortable" class in the apps
T232046: As a reader using the iOS app I would like to be able to sort tables
Here's the feature in action on desktop:
Enabling it on mobile is trivial (mw.loader.load('jquery.tablesorter'); $('.sortable').tablesorter();' ) and I'm surprised a gadget hasn't done it out of frustration of this ticket being open so long.
On mobile the code is functional, however looks a bit odd. We likely want to tweak the CSS to fully fix this issue (a small amount of work)