1. Swipe left to open settings and select "Add Integrations." 

Note that integration with Slack is a premium feature, in order to access it you will have to join the premium beta. 

2. Select the integrate button next to Slack. 

You will be redirected to Slack's authorization page, select your team and authorize.
 

3. You now have Slack integration. :) 

Select the "return to WhereDat" button.

From WhereDat, try searching for something you recently talked about on slack.