Really great Joomla tool Cook is a great piece of kit for creating Joomla components. It uses a drag-n-drop interface to build tables and fully featured pages. You can test your component in a sandbox before downloading it packaged up ready to install. The developer is responsive on the support forum.
Twev (JED)
          

Although I found this tool some time ago I just started learning experimenting and building this first component on Monday and now on Thursday afternoon it's already online. Although I already had a working version done with another tool this is much easier to build and at the end you have the freedom to own your own component. Once you know how to use Cook you will boost your productivity as the learning curve is really moderate compared to many other tools.
Giori (Forum)

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