Alternativer til ZeroMail til Windows Mobile med kommerciel licens

• Windows Mobile
  Alle platforme Windows Mac Linux Chrome OS Android iPhone Android Wear iPad Android Tablet Kindle Fire Windows S Web Self-Hosted Software as a Service (SaaS) PHP Windows Mobile Java Mobile S60 Android TV Chrome OpenPGP S/MIME DAVdroid
• Kommerciel licens
  Enhver licens Gratis licens Open Source-licens Kommerciel licens