The final entrant in the three-way online money management competition between Mint, Wesabe, and Quicken Online has released an iPhone app, and Quicken Online Mobile aims to differentiate itself from the pack in a few ways.

How exactly? Much like Quicken’s free online service, but similar to Mint and Wesabe, Quicken Online’s app is intended for those not wanting a laser-focus look at the details of their money flow and investments, but folks just looking to know how much they have now, where it is, and when the bills are due. You know, normal everyday stuff.

But Quicken, in addition to the usual balance and account updates, also starts you out on a page that shows how much money you have left to play with before your next pay period, with bills and other necessities factored in. The idea, presumably, is that you can whip out the iPhone and look at how close you are to the edge of debt before deciding that, yeah, you can pay for that round. The iPhone as a useful everyday business tool? Who would’ve thought it?

Coolest of all, perhaps, for the crowd that wants something more or different than a stack of numbers and financial forecasts, is a nearby ATM location tool that uses your iPhone’s GPS or Wi-Fi triangulation to get you to a money machine when you need one. Early reports are that it works pretty well.