Dwell clicking software that supports right-dragging and allows to define shortcuts

DwellClick is a nice dwell clicking app on mac that is customizable, versatile, as well as nice-looking. The following pictures show the hands-free panel and the pop-up panel of the app.

Hands free panel Pop-up panel

It supports most of the features you mentioned:

single/double click, drag, drag & hold
keyboard shortcuts for changing modes
hands-free panel that stays on top
customizable dwell clicking time

In addition, there are other features such as:

modified click with ⇧, ⌃, ⌥ or ⌘
pop-up panel near the mouse pointer to select different modes

The only modes missing from your inquiry are triple click and right drag, but I don't think Mac OS uses these modes. However, it should be easy to configure a desired short cut or action to the modified clicks using BetterTouchTool mentioned above, so that you can use them instead.

Haven't seen anything on Dwell for mac unfortunately. I've started playing with BetterTouchTool since Jitouch hasn't updated for Yosemite. BTT seems more versatile if not as nicely predefined. BTT enables assigning actions to trackpad gestures or mouse. I don't know how to integrate dwell clicking, sounds interesting.

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