Traditionally, the roll out of new hardware prompts a rush of software sales in the days after launch. For developers working on iOS, however, the wait for iPhone 4S prompted a slowdown.

User acquisition platform Fiksu has claimed the long run up to the unveiling of new iPhone hardware resulted in a short-term drop in app downloads according to numbers sourced in August and September.

The firm's study claims downloads dropped from 4.06 million downloads in August to 3.8 million in September, based on Fiksu's App Store Competitive Index.

No surprise

As a result, Fiksu reports, app marketing costs on the App Store reached a record high.

Fiksu reports the marketing cost per loyal app user rose by 10c to $1.64 in September - a six percent jump from $1.54 in August.

"It's no surprise to see downloads continue to drop in September, as they did last month, as consumers eagerly awaited the release of Apple's newest iPhone," said Micah Adler, CEO of Fiksu.

"Now that the iPhone 4S is available – and, with four million models sold over its launch weekend – we can certainly expect next month's Fiksu Indexes to paint a markedly different picture. Early indicators already point to an increase in October's app download volumes."

[source: Fiksu]