A minor suggestion,

I have found the best way for me to manuver my way around the Voice Cards is to constantly return to the Voice Card Index.

This not only allows me to follow a particular train of thought, but will also let me see what cards I have already seen.

Would it be possible to include a button to do this a bit more elegantly than using the comand R function.

[Editor's note: You already have such a button! The bent arrow button in the lower right-hand corner will instantly return you to the index card!]