When Apple debuted its iAd service it required a minimum investment of US$1 million from advertisers. Now with the first run of iAd campaigns ended, Apple is lowering its minimum spend to appeal to smaller-scale advertisers that originally couldn’t afford the platform, according to “All Things D” (http://macte.ch/ILBgW).

The new entry point is $500,000. “This new minimum buy is a great step forward and a necessary one, I think,” Mark Read, CEO of WPP Digital, the digital arm of global ad giant WPP, told John Paczkowski of “All Things D.” “Lowering the minimum buy to $500,000 from $1 million will certainly make the platform more appealing.”

iAds combine the emotion of TV advertising with the interactivity of Internet advertising, according to Apple CEO Steve Jobs. He says that iAds, which are built into iOS 4, allow users to stay within their app while engaging with the ad, even while watching a video, playing a game or using in-ad purchase to download an app or buy iTunes content.

In late December, Apple rolled out its “iAd Producer” app so people outside of Apple can make iAds. “Business Insider” (http://macte.ch/OPTUF) says the question with iAds is still whether Apple can deliver enough revenue to publishers to stand out from competitors like Google, Millennial Media, and others.

— Dennis Sellers