Fiksu, a mobile app user acquisition platform, today announced two new indexes to help app marketers in their quest to get new mobile app users.

Competition for rank in the app stores indexes how many downloads are achieved per day by the top 200 apps in that store. The second index deals with the cost to acquire “loyal users,” those who open an app three or more times.

The data so far reveals that the top 200 iPhone apps in the U.S. averaged about 4.34 million downloads per day between March and June. The cost per user has risen to more than a dollar, to $1.08.

What does this mean to the app developer? According to Fiksu, developers and marketers can use the data from the top 200 iPhone apps to gauge how their own efforts to market their app stack up against the industry at large. In addition, the indexes can be used as a way to understand how variables such as iOS upgrades, sales of devices, advertiser demand and network advertising inventory can affect business goals. In other words, if there is a spike in downloads of the top 200, developers might expect a slip in downloads of their own non-top-200 app. Or, a lack of advertising space might help app publishers know that their per-user cost will be up within a current month.

More key data points from the March to June 2011 period include:

- App Store Competitive Index: April 2011 was the most competitive month–the Top 200 ranked free iPhone apps amassed an aggregate average of 4.610 million downloads per day. In May, this dropped to 3.78 million downloads per day but in June rose again to 4.505 million per day (a month in which Apple reported one billion total downloads).
- Cost per Loyal User Index: The index reported a steady increase: from $0.94 in March to $1.10 in May and $1.27 in June.

To read the full analysis and see the data, go to Fiksu’s Index pages.

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