Of the tools and services for developers we asked about in our last survey, one category stands out by miles as having the wealthiest developers: voice services. If we exclude developers earning over $50k per app per month (as we typically do for other tools categories since a small number of successful developers can heavily distort the data) from those interested in money and reporting their income to us, then those using voice services earn an average of $4379 per app per month. This is a similar level of revenue to those using crash analytics services, which we’ve already shown is correlated with financial success. However, excluding those earning over $50k per app per month is rather unfair for voice services since this is almost 10% of developers using this tool category; if we include them, the average rises to $13410 (the comparable figure for those using crash analytics is $8764). Of course there’s a lot of variety in the voice services sector and the revenue is not at all evenly distributed.

Popular is not always profitable

In order of popularity, the most used services in our survey were Twilio, Skype, Mircrosoft & Tropo. Of those, the best in terms of revenues, Tropo, had 77% of developers above the “app poverty line” of $500 per app per month, whilst the worst, Microsoft, had 77% earning below that level of revenue. Outside of the top four services by popularity, there was a wide range of developer success but the average revenue was very close to the average for the whole category.

Skype is an extremely popular consumer service but their services for developers, particularly mobile developers, are quite limited in scope. SkypeKit, which is their offering for embedding Skype functionality in devices and other apps is not permitted to be used in mobile devices. Although Microsoft has similar capabilities to Twilio and Tropo through their acquisition of TellMe that is not yet fully integrated into their standard developer offering. If they try to use their capability to differentiate the developer offering for Windows Phone then it’s likely to remain limited by the success of their mobile platform.

Isn’t voice commoditised?

Whilst having voice services tied to a single platform is not ideal, cross-platform availability is not critical. Developers whose main reasons for selecting their service included cross-platform availability earned a below average for the sector but still very respectable $8120 per month. Those focused on call quality did slightly worse, while developers whose primary concern was cost did very poorly at only $2280 per month on average. At the top end of the spectrum, the only reasons correlated with revenues above $20k per month were feature set and scalability. The feature set breakdown in our survey makes it much clearer where the bulk of the money is being made by users of voice services. Fortunes are not being made by delivering generic VoIP services to giant user bases; in fact, the average number of active users for the most popular apps of developers across the whole voice services sector is only about 27,000. On the contrary developers using voice services for inbound calls averaged $25k per app per month, while those using intelligent call routing and/or Interactive Voice Response (IVR) systems averaged $30k per app per month. While it is possible that there are some developers doing good business using these cloud services to replace legacy IVR services or extend the reach of such services to smaller businesses, it’s very likely that many of these developers are building customer services channels for their own apps. In this case there’s some survivorship bias here – only fairly large and successful businesses would build out such complex customer services systems. Also it’s quite likely that businesses that need voice and SMS based customer service channels are about more than just an app, in which case the revenues associated with the apps may reflect sales of external goods, services or content and are thus not directly comparable with those of developers purely monetizing through paid downloads, advertising or in-app purchases (although all of these revenue models are used by some developers using these voice features).

Consider the costs

When you consider that numbers rented, call minutes and SMS’s sent all have associated costs from the voice services provider it’s not so surprising that a typical voice services developer has higher revenues – they need to in order to stay in business! The existence of these voice platforms is strong evidence that basic voice is commoditised and there’s very little room for differentiation or profit simply packaging and branding such services for consumers. So, while the revenues for all kinds of voice app are higher than average, the associated costs are higher too. Those developers that capture significant value with voice services are using them to add value to some other service, rather than trying to re-sell them directly. That said, these services are very easy to use and relatively inexpensive. It’s worth thinking about ways you could use them to build better relationships with the customers for your app business.