July 19, 2011

In Search Of: API Metrics - Total number of Applications


Last week, we began our Developer Metrics series of exploring the top three most commonly reported developer metrics. We kicked off the series of getting at the value of measuring bigger versus better with different ways of reporting on Total number of Developers who are consuming your API.

This week, we're taking a look at a few of the different ways companies measure and report total number of applications. Twitter recently reported 1M registered applications in July. In May, Apple announced 500K approved iOS applications (400K active in iTunes) and Google announced 200K applications available in the Android Market. Facebook currently reports its application activity in terms of users installing 20 million applications daily.

Total number of Applications
Application numbers reflect developer adoption and provide insights around end user activity and developer market opportunity around your API platform. Do you count applications based on what developers fill out as part of their registration flow? By number of active API keys with minimum of API call volume (which can underrepresent number of applications when they often use the same key or can overrepresent number of applications if multiple keys are often required for a single applications.) Or do you count applications only when they are submitted for app certification or approved to appear in your application gallery? 

At Mashery, we advocate focusing on the number of active applications in the short term to reflect the pulse of developer adoption and opportunity, then moving towards measuring approved applications and user installations as your ecosystem grows.

    Bigger: Total applications = an application registered by a member developer
    Better: Active applications = an application with minimum level of production environment API call volume in most recent month/quarter/year

The downside of reporting on active applications is that the number fluctuates and sometimes goes down(!) This may not sit well with groups who like to report numbers that only grow up and to the right. Keep measuring it anyway. Today's app economy reveals that there are not only big evergreen apps, but also event-based apps with a shelf-life that grant an end user wish at the right time/right place.

We think it is better to focus on what developers are actively building in the last quarter or so to uncover which areas of your API opportunity are growing and which are shrinking in order to focus program resources and support appropriately. Resist the urge to only measure reported PR numbers. Measure and manage numbers that will result in good developer experience and opportunity.

Next up: we wrap up our series on developer metrics with a look at measuring Total API Call Volume. Hint: bigger is not always better. :)