Smile has been around for a while. I can't believe it is 2016 and I have become even more a fan of it now, mostly because of it being such a useful R(apid) A(pplication) D(development) tool. More on that in a bit.
There are a few drawbacks:
1) The developers (Satimage, France) spent a lot of energy –in the early days – on getting the word out and getting the documentation built, but it seems they kind of ran out of steam, probably because of the lack of demand in a niche market. So getting help can be frustrating. At this point they suggest plugging into their users list, but that can be frustrating, too, by my experience.
3) Though updated semi-regularly, the updates at this point are not major. Unless Satimage gets a shot of inspiration, ambition or capital, Smile pretty much is what it is, I think.
All that being said, for most script-writing, Smile is wonderfully clean and feature-rich. The Satimage Scripting Addition included makes the app worth the download, arguably, and the application itself is incredibly script-able (not record-able) and attachable. You can even hack the app if you're really adventurous, because much of its innards are AppleScript-built. And if you do look through those innards, it is a wealth of teaching material.
About the R.A.D. capability:
You can build superbly functional (and complex) interfaces to use with Smile and save them as dialog files. Each of these becomes like a plugin for the app. Using the dialog creator, I've created, to help assist in my work (or for fun):
an ffmpeg-based video transcoding tool, which does everything I want and need to post updates of video pieces (in any format) I'm working on for clients and employers;
automated scanning software for scanning (for example) hand-drawn animation;
the best animated GIF creator I've ever used;
a UI for changing various properties of individual "notes" (mark-up highlights, textual notes, boxes, lines, etc.) of a pdf document in Skim (another great free app);
There was a time when doing rapid AppleScript UI development meant using something called “FaceSpan”. The way FS worked made it ideal for making user interfaces at an unparalleled pace. FaceSpan is gone, and the only thing close to the level of speed and ease in creating AS-based UIs is Smile and its dialogs.
I hope Satimage can keep the Smile script editor going. I find it a great resource. And it’s free.