CloudNine is described as 'Empowers legal and business professionals with eDiscovery automation software and professional services that simplify litigation, investigations, and audits for law firms and corporations' and is an app. There are five alternatives to CloudNine for Web-based, SaaS, Windows and Self-Hosted. The best CloudNine alternative is Everlaw. It's not free, so if you're looking for a free alternative, you could try GoldFynch eDiscovery. Other great apps like CloudNine are KCura Relativity, Wind and Logikcull.