Camunda - The Universal Process Orchestrator
Modelio - Modelio is an open source modeling tool supporting natively UML, BPMN and model exchange with XMI.
Bizagi - Bizagi is a Business Process Management (BPMS) solution for faster and flexible process automation. It's powerful yet intuitive BPM Suite is designed to make your business more agile.
Diagramo - Diagramo is an online flowchart software - diagrams (create, edit and share)
Celonis - Celonis offers process mining tool for analyzing & visualizing business processes.
UML Designer - UML Designer provides a set of common diagrams to work with UML 2.5 models.