Plumm is described as 'Single collaborative customer support dashboard for all of your projects. Chat with your customers and your team members using single workspace. If it's an email sent to support@yourproject1.com or a chat request from yourproject2.com, it all goes into the same Plumm inbox' and is an app in the business & commerce category. There are more than 100 alternatives to Plumm for a variety of platforms, including Web-based, Android, iPhone, Windows and Mac apps. The best Plumm alternative is Thunderbird, which is both free and Open Source. Other great apps like Plumm are Element, Discord, Matrix and Slack.