LinkedIn Answers: What are the PDA killer apps? Of course email and contact management will always be "the" killer apps, but I'm guessing your question concerns applications that are extras.As a consultant who's often on the road, the killer apps for my Treo 650 are Google Maps and TreoAlarm.Google Maps is much more than going from point A to B. It can show you nearby businesses (what's the closest Barnes & Nobles?) and show cu By HandsOnin Public bookmarkswith apappsmobile