Nevertheless I think signature is one of the 2 only thing that miss in Macdive. It is important to have signature on your dives here in France if you want to pass a new grade and it is possible only on Divelog right now. We hope to have it soon
The other one feature is to be able to merge data about same dive; i mean data filled on iPhone/ iPad and downloaded on our Mac. Most of us (I think) cannot take its computer when going to dive. Therefore this feature could allow to merge data filled "on the field" (including signature

but its is only an idea
