Downloading DeltaChat 1.30.0 for Mac from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this app available. The actual developer of this free software for Mac is Delta Chat contributors. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe. The software is categorized as Communication Tools.
From the developer:
Delta Chat Desktop is a messenger that uses the existing e-mail server network. Technically, Delta Chat is an e-mail application but with a modern chat interface. You just use your standard e-mail account and start chatting with any of your e-mail contacts, whether they have installed Delta Chat or not. Recipients will see a simple e-mail and may directly reply with their own e-mail app.
You may want to check out more software for Mac, such as iChatOnLogin, MySpaceIM or TextMagic Messenger, which might be similar to DeltaChat.