Note that Dr. Allan's work has been updated a few times.
So now, there's:
1. Allan Deviation - which almost no one uses anymore.
2. Overlapping Allan - very common. This is now considered the 'standard' version.
3. Modified Allan and its overlapping version.
4. Total Allan and its overlapping version. This is my favorite because it gives you a longer graph than any of the other versions for a given dataset.
There are others beyond that such as Hadamard and Theo 1.
Each version tends to inflict a heavier computational load than the ones earlier in the list.
A few programs that use Allan Deviation and some of its offshoots are Timelab, Stable32, Plotter, and Alavar. Timelab is updated regularly, Stable32 and Plotter are not. I'm not sure what the status of Alavar is.
Ed