Alternativ till SlideMail för PortableApps.com med kommersiell licens

• PortableApps.com
  Alla plattformar Windows Mac Linux Chrome OS Android iPhone Apple Watch Android Wear iPad Android Tablet Windows S Web Self-Hosted BSD Haiku PortableApps.com Slack F-Droid Chrome Ruby Gmail Cloudron Amazon Echo (Alexa Voice Service) PureOS (Purism)
• Kommersiell licens
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