DMDrep app at the itunes store can be downloaded for free - its like an electronic business card. Check mine out and if you hit the Information link at the top of the screen, you can learn how to have your 'own' iPhone app too!
Here is the link http://itunes.apple.com/ca/app/dmdrep/id348635670?mt=8
I also like Bump http://itunes.apple.com/ca/app/bump/id305479724?mt=8 which allows you to 'bump' your phone with other iPhone users and share information immediately
For the Blackberry, I would suggest Dr. Bicuspid (search in the Blackberry app store) to keep up to breaking headlines relative to our industry.
I also like Vlingo which allows me to text, email and search using voice - very handy when your hands are otherwise occupied
I have several other great apps - like The Score (keeping up with sports scores) and Echofon which I use to follow and organize my Twitter feeds.
Another great app is the Facebook app of course - many phones now just have this app built in!
I've been an Act! user for about ten years or more, my Act database and calender run my life. A very useful app is Companionlink. This add on updates and shares data between my Act program and my blackberry. It syncs both ways so as long as I remember to allow them to "chat" via bluetooth daily life is good. I highly recommend Companionlink, nice folks with good support as well.
I use drivesafe.ly which is a Blackberry app. It will read your texts and email messages to you while you are driving. There is a free version and a more robust version that you pay for. The free version only reads the first 25 words or so. Better than looking at your emails while you are driving.
After a bunch of recent memory lapses regarding passwords I have just discovered Password Keeper for the Blackberry. Now I only have to remember the password for the Password Keeper. Oh, I also have to remember to enter all the various websites, programs, etc. and their passwords, but only once!