Marketing firm Fiksu has launched two new mobile application indexes that will of interest to both app developers and marketers alike. The indexes provide insight into industry averages related to app downloads in top app stores as well as the costs associated with acquiring new users.

App Store Competitive Index

Initially, the Fiksu App Store Competitive Index will focus on iPhones applications, but will be later expanded to Android, the company says. The data for the index comes from nearly 2 billion mobile app actions, including app launches, registrations and in-app purchases, all of which are recorded by apps marketed via Fiksu’s mobile app user acquisition platform. So while it’s a large data set, it’s also a data set that represents certain types of applications more heavily than others – that is, those engaged in and paying for user acquisitions.

The current data, which tracks the months of March through June, shows that April was the top month for downloads during this time frame with 4.610 million downloads per day among the top 200 free iPhone apps. In May, this dropped to 3.78 million downloads per day. It then rose once again last month to 4.505 million.

By tracking these figures, publishers and brands can help better understand their own app’s ranking changes, in comparison with others on the charts. The indexes may also be a source of insight into how other industry moves could be impacting app sales, including things like iOS upgrades, device sales, ad inventory changes and more.

Again, this data is most relevant to those closely tracking the effectiveness of their own marketing campaigns.

User Acquisition Costs

The second new index, the Fiksu Cost per Loyal User Index, tracks the average cost of acquiring new application users for those brands that engage in app marketing techniques. It, too, is iPhone-only for now.

At present, the average acquisition cost is $1.08, Fiksu found. This number represents a steady increase from $0.94 in March to $1.10 in June.

Both tools could certainly function as worthy complements to whatever trend-tracking, analytical resources developers, publishers and brands already have at their disposal. However, as with anything, these indexes shouldn’t be used alone. Downloads and user acquisitions are fine indications of an app’s performance, but they’re not the only ones that matter. Other metrics like length of app use, how often an app is used/engagement, how many users are attained/lost (e.g. churn), app removals, revenue earned, number of upgrades, and more are also worth tracking just as often.