I like to to check/add tasks throughout the day while I'm on the go. A mobile app that would allow me to do that quickly and easily would be really valuable for me.
No need for a full additional app, but upgrading your website to a react/angular/vue pwa would do the job perfectly!
With slack mobile app you can check/add manage your or team members task with this slash commands.
/todo Post on Facebook @Brad Nov 13 - add task with assign + due date
/todo list - all task in your workspace per chanel
/mytodo - all your task.