You must change your Slack password if you used the application on Android, according to an email sent by the company and published by Android Police. Apparently, from December 21 to January 21, the Android version of the Slack app would store users’ credentials in plain text, which theoretically means that any other app on your phone could have access to them.
If you have the popular communication tool installed on your Android phone, the first thing you will want to do is update to the latest version of the Play Store, as changing your password will not work if you are still running the old version. So, if you received the email from Slack, you can click on the link to change your password. Otherwise, you will have to reset your password on a desktop computer using Slack’s instructions.
First, login to Slack and go to your profile, which can be accessed by clicking on your image in the top right corner of the application or web application and clicking View profile. Then click the More button and Account Settings. From there, you should be able to change your password, although it is important to note that the option is not available if your organization uses Single Sign-On.
Of course, if you used your Slack password on other sites, you should change your passwords for them as well (preferably something exclusive).