Free Sells Itself
When I tried promoting Blocfall Free, a free, ad-supported version of my app, the story changed. I still had most of the $250 that I'd transferred to Flurry to participate in its system and if I wasn't going to make any money selling the app, I might as well try to build a user base and hope that the AdMob ad in the app would generate some return.

I bid $1 per install (despite a recommendation that bid averages were close to $4), with a $100 daily spending limit, and let my ad -- a template supplied by Flurry -- run. When I checked back later in the day, I was stunned: I had over 2,500 installs. By the time the campaign concluded, I had 3037 installs. If there's a lesson here, it's the obvious one: People really like free things.

I was immediately worried that I'd be held liable for the bill -- having spent some time in the film businesses I'd seen film distribution contracts that made signatories responsible for the distributor's ad costs. At $1 per install, I could be billed for $3037, less my initial payment. After checking the terms of service and making sure that I had in fact set a daily budget of $100, I inquired to Flurry about the situation and was assured that I'd only be billed based on the budget I submitted.

Advertisers are never charged in excess of their specified budgets I was told.

So in effect, I received about $2750 in advertising at no additional cost, free money in a manner of speaking. To look at it another way, Flurry is currently providing app installations for ten times less than list price, for about the cost of a click. In the context of mobile games, installations are worth far more than a click.

Business operations manager Aakrit Vaish explained what was going on in an e-mail.

"Free apps are in high demand in our system right now," he wrote. "And by the time the system sent out the first set of impressions through our network, the conversion rate was so high that we overshot the budget by such a significant amount. We are in the process of improving some of the factors that determine ad optimization."

I repeated the experiment on Wednesday and the results were similar: The several thousand installs my app received ended up costing about $0.13 each, despite a minimum bid of $0.75 per install. At least until Flurry tightens its system, the company's App Circle CPI offering has to be one of the best advertising opportunities for mobile developers out there. And perhaps afterwards too.