Small name changes

[marcglasberg]

1. iteratorAtEnd is really confusing. It should be called reverseIterator or iteratorReversed.

2. A lot of methods have their parameters called other. I would prefer to call them sequence. For example: bool startsWith(Characters sequence) instead of bool startsWith(Characters other)

Of course, this is a matter of taste, so feel free to disagree.

[lrhn]

The iteratorAtEnd is not a reversed iterator. You don't use moveNext to move backwards like I'd expect for a reversed iterator.
It's just an iterator which is currently at the end, just as if you had done var it = chars.iterator; while(chars.moveNext());.
So, the name is precise.

Not sure what sequence would add. It's a new concept (we use "sequence of characters" to say what a Characters object represents, and occasionally use it implicitly about the sequence of characters of a Characters object, but we don't "sequence" as a stand-alone noun).
If anything, I'd use characters instead of other. That would actually be better.

[marcglasberg]

Ok, at the time I wrote this I didn't understand that Characters.iterator is not a traditional iterator, and can move both directions. I'm not sure but I believe this fact was not clear in the docs at the time.

I agree with bool startsWith(Characters characters)