’s New iPhone Apps Are Big Time Savers, the folks behind the free Phonebooth system that’s such a boon to web workers, today launched two new iPhone (s aapl) applications targeted at consumers and small business customers: Holdr and Conference Starter. The software was developed under the Phonebooth Labs name and marks the company’s first step into the mobile software marketplace to complement its VoIP offerings.

Holdr is the more consumer-focused of the two: Instead of wasting time being tethered to your phone as you wait on hold, Holdr allows you to press *7 and hang up. When the other end of the line takes your original call off hold, Holdr rings your phone back to reconnect the call, which should then be with a live person. The one downside I can see is that you have to initiate the call from the Holdr app, not the standard iPhone dialer. With that in mind, I’d probably only use this free software when specifically calling a place of business.

Conference Starter, meanwhile, looks to be an excellent way to get up to 25 people on a conference call. Using the $4.99 app, you select contacts, choose a conference moderator and click the Start Conference button — each of the selected contacts are then called by the service and upon pickup, each is added to the call. The first 250 minutes of conference calling using Conference Starter are included in the application price, but after that, each additional minute is 2 cents. Conference Starter supports in-app purchasing of additional conference minutes and works on the iPhone, iPod touch and iPad devices.

Given the kerfuffle over Apple not allowing a Google Voice (s goog) app on the iPhone, I’m almost surprised that both of these apps were approved. Then again, Apple could be facing some antitrust scrutiny in the near future, so it may behoove the company to be more liberal with third-party software than it has been so far.

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