Download of httpserial 1.1.5 for Mac was on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The software lies within Developer Tools, more precisely Webmaster Tools. The actual developer of this free Mac application is CodeByMath. 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.
From the developer:
httpserial bridges a connection between the HTTP protocol and serial devices on your computer. This app was specifically written for serial devices connected to a USB port, such as the Arduino, or other microcontroller. This allows for communication with such devices using only your web browser. With this app running, you can send data to
serial devices directly from URLs in your browser's location bar, or by using Javascript.
You may want to check out more Mac applications, such as QuickMenu, Adobe Shockwave or Image2Web, which might be related to httpserial.