Slack brings threaded messaging to its mobile app, here is how it works
Here is how it works, as explained by the developers. First of all, once you or someone else posts a message in Slack, you can start a detailed conversation on that particular topic by hovering over the message and clicking Start a thread. Once the right sidebar in Slack will open, you can add your reply.
Keep in mind that replies to a thread won't mark the channel as unread or notify you if you're not directly mentioned. This is only available for regular messages posted in channel.
It's also worth noting that all threaded conversations are archived. Also, you can search them for specific information and context if you don't want to read the while conversation, which comes in hand especially when it gets too cluttered.
Moreover, Slack users can now participate in multiple threads if they wish so, especially since the update adds the new All Threads view, where users can read and reply to these conversations.
According to Slack developers, the new threaded messaging feature is rolling out to mobile devices over the next few days, and it will be available on the desktop version of the app as well.