The button-up BlackBerry has held the title of unofficial phone of business people for years, but now Apple is looking to encroach on its turf.

It started with a TV ad back in April.

“Say you own a small business, and you need to ring up a customer’s order,” the voice intones as the finger scrolled through iPhone applications that process credit cards, print invoices and ship products.

You’ve probably seen on prime-time TV a time or two. Here’s a refresher.

That was just the beginning. New iPhone applications geared to small businesses are popping up at startlingly rates as developers push to tap into young professionals and entrepreneurs.

Preliminary research indicates Apple’s strategy could be working. Roger Entner, head of telecom research for The Nielsen Co. told the Wall Street Journal last week that iPhone use is up at small companies — especially those with between 15 and 99 employees.

Medium-sized firms tend to be more restrictive when it comes to employees using interactive technology, he said. But larger employers are more lenient, probably because they have more resources.

There are a number of apps small business owners might want to check out, including Billing Manager for invoice processing, Tripper for millage tracking, QuickBooks for access to popular accounting systems, and plenty of others.

When it comes to smart phones, is iPhone outpacing BlackBerry? You decide, and tell us in the forum below.