Alternativy k Tinyinvoice.com pro Slack s bezplatnou licencí

• Slack
  Všechny platformy Windows Mac Linux Android iPhone Windows Phone Apple Watch iPad Android Tablet Kindle Fire Web Self-Hosted Software as a Service (SaaS) Slack Electron / Atom Shell Chrome Cloudron
• Bezplatná licence
  Jakákoli licence Bezplatná licence Licence Open Source Komerční licence