Kissflow - Kissflow is a workflow tool & business process workflow management software to automate your workflow process. Rated #1 cloud workflow software in Google Apps Marketplace.
Camunda - The Universal Process Orchestrator
Nintex - Cloud-based digital workflow management automation platform
SyncTree - SyncTree is a SaaS-based Super Connecting Platform that connects any services you want
ProcessMaker - ProcessMaker is an easy to use BPM and workflow software solution. It is used to design, automate, and deploy business processes of any kind.
jBPM - jBPM is a flexible Business Process Management (BPM) Suite.