Alternativas ao Site Down para Software as a Service (SaaS) com licença comercial

• Software as a Service (SaaS)
  Todas as plataformas Windows Mac Linux Chrome OS Android iPhone Web Self-Hosted Software as a Service (SaaS) PHP BSD Slack Discord Twitter Mattermost
• Licença comercial
  Qualquer licença Licença gratuita Licença Open Source Licença comercial