Alternativas ao Letterspace para Software as a Service (SaaS) com licença de código aberto

• Software as a Service (SaaS)
  Todas as plataformas Windows Mac Linux Chrome OS Android iPhone iPad Android Tablet Kindle Fire Web Self-Hosted Software as a Service (SaaS) Firefox Opera PortableApps.com Chrome Visual Studio Code Termux
• Licença Open Source
  Qualquer licença Licença gratuita Licença Open Source Licença comercial