It would be best if you can, for example, about the history making single deleted or altered by synchronizing contacts and appointments undo it.
It would be enough if this function is available per session.
I had this problem.
I have an HTC WM6.5 with HD2 and after installing the beta-s, it has created some contacts on my HD2 twice.
The next time he wanted to delete the duplicate.
However, he has the contacts on the HD2 and deleted my Thunderbird.
So then they were completely gone ...
And with an undo function would solve this easily.
Hope this is understandable?
p.s. the collation of the history would be better if the recent actions stand up and not down
