I’ve used Midnight Apps‘ Cha-Ching applications to manage my transactions on-the-go, but the developers haven’t released any updates or posted any news on their site, so many consider the applications dead. This is a shame because I loved their interfaces (though quirks abounded) and syncing to/from iPhone/Desktop was so easy.
I’ve gone through a couple different apps trying to find a replacement. Apps like the beautiful Expenditure left me craving simple functions (reconciling?). Others were just hideous (I can’t remember the name, but it cost $1.99 and had an ugly orange interface).
Yesterday I bought Accounts [iTunes link] for iPhone (at $0.99). It’s not as pretty but it’s almost as functional. Try the full or free version out.