A number of third-party ad providers are reporting early success with Facebook’s new mobile-only Sponsored Story advertisements.

Nanigans tells us that its mobile campaigns have an average 45 percent lower cost per click than those on desktop. In some cases, CPCs have been as low as $0.20. The company has also found mobile Sponsored Stories to have an average 12 percent higher clickthrough rate than those on desktop. When combined with interest targeting, CTR has been as high as 2 percent.

These results support what others are reporting. TBG Digital shared data with TechCrunch that showed mobile Sponsored Stories with an average CTR above 1 percent and CPCs on average 2 cents lower than those on desktop. Besides being effective for advertisers, the new ad type seems to earn Facebook more per impression, as indicated by eCPM in the chart below.

AdParlor says it has seen an average mobile CTR of 0.821 percent, which is 25 times better than traditional Facebook ads. AdParlor CEO Hussein Fazal says that with the high CTR, Facebook’s system has suggested bids as low as $0.02 to $0.04. And because Facebook limits the number of Sponsored Stories it puts in users’ mobile feeds, a campaign’s frequency doesn’t get too high and drive down CTR. Here are the exact results from one of AdParlor’s mobile Sponsored Story campaigns.

AdParlor found the conversion rate of users who click a mobile Sponsored Story and then Like a page to be lower than it is on desktop — 55 percent versus 72 percent — but the higher mobile CTR makes up for this, Fazal says. This is to be expected because mobile pages do not have custom landing tabs. However, Facebook has been testing different designs for mobile Sponsored Stories to make the call to action more prominent within users’ News Feeds. Conversion rate might also improve whenever Facebook updates its mobile site and apps to show pages in the Timeline format.

New ad units tend to have higher CTRs and lower CPCs when they first launch since there is some novelty for users and little competition driving up bid prices. Although it is too early to make claims about the overall effectiveness of Facebook mobile ads, advertisers who begin mobile campaigns now are likely to see their dollars go a lot further than they would on desktop. Besides using mobile Sponsored Stories for page-Like campaigns, the new placement could be especially valuable for retail offers and mobile app promotion.

For now, mobile-only Sponsored Stories are available through the Ads API and Power Editor, not the self-serve dashboard.