RunaWFE - RunaWFE Free is a free Open Source BPMS (business process management system), which serves to optimize and automate business processes (for Windows, Linux, Mac OS).
DoDone for G Suite - Dead simple project managment with digital post-its. A no frills project management tool which enables you to oversee all of your shared and individual tasks in one place! #clean #lean #collaborative. Built on Google Drive
Camunda - The Universal Process Orchestrator
BP Simulator for G Suite - Business process simulations modeling tool
Joget.org - Open Source Workflow Software, Business Process Management and Low-Code Application Platform.
Mail Merge for G Suite - Create your mail template as a draft in Gmail and merge it with your Sheet data. You can use this syntax: {{Column Header}}