Data from Apsalar’s Big Data Lab reveals the game categories with the highest propensity for in-app purchases. As it turns out, strategy games are more than 18x more effective at driving IAP than arcade games! In-app purchases are also strongly correlated with engagement (as measured by average daily session length). Yet another proof point that user engagement is a key ingredient in any app monetization strategy.

Testing any mobile app presents a wide range of challenges. The often repeated but rarely followed software best practice of test early, test often is harder to adhere to than usual due to the fragmentation of the target environment and the relative maturity of tools. The increased acceptance of apps by mainstream consumers and intense competition have raised the bars for user experience and quality. There is more to test than ever, yet often very limited budget for doing so. Fortunately every challenge presents an opportunity and a vast array of tools vendors are racing to fill the gaps.

Alexis Piperides, co-founder and CEO of Proto.io, takes us on a tour across the fascinating landscape of prototyping tools. In these early days of iterative design of mobile applications, can tools and services help to drive perfection?

Voice communication is one of the core functionalities of every mobile phone. However, telephony is up for a big shake-up, as Internet telephony companies like Skype and voice application platforms like the ones below are challenging century-old assumptions about how people speak with each other remotely. Voice Application Platforms allow you to make creative solutions that integrate voice communication deeply in your app: as voice messaging, click-to-call, person-to-multiperson, voice search and more. But despite catering to many use cases, their use is relatively low among developers. An opportunity to stick out of the pack?

On the surface, advertising seems like a fairly simple and easy to implement business model for an app. Decide on some places to display ads, integrate one or more third party ad services and wait for the money to start rolling in. If you do this without a clear plan for how and why users will interact with ads in your app you’ll probably find the revenue disappointing. Optimise revenue by growing your user base, increasing engagement…

User analytics services are becoming increasingly important as competition in app development continues to rise. The ability to track how users interact with apps is extremely valuable for both developers and product managers and to some extent acts as a proxy for user feedback. The absence of a direct two-way communication channel between developers and users means that user analytics often provide the only channel from user to developer. 28% of developers use user analytics services overall…

Ahead of the release of our latest Developer Economics survey, we look back the biggest challenges developers reported in our 2012 survey. Here we discuss six of them, with some basic tips on what to do about them. The challenges are split between marketing and post-launch app and user management. The three biggest marketing challenges were: keeping users engaged, targeting the right users and identifying the right revenue model. The three biggest post-launch challenges were: Tracking bugs and errors, getting users to review your app and updating applications in the field.

Elliot Schmukler from LinkedIn spoke at a recent Growth Hacker conference about the strategies they’d used to grow the site since he joined in 2008. His advice was very helpfully summarised by Sandi MacPherson, Founder at Quibb and is general enough to be applied to mobile apps. Read our take on his main points.

Currently the vast majority of mobile app advertising is used to generate new installs. At the same time, for some of the most successful revenue models, a small fraction of the most active users generate the bulk of the revenue. Free-to-play games are a good example of this model but there are similar in-app purchase driven schemes in other categories. Whilst a user is still very engaged with an app it’s likely that the most cost effective way to increase their spend is within the app. However, if an existing user stops regularly using an app then might there be more value in tempting them back in than acquiring a new user?

The latest trend in app development is targeting companion screens, as a way to bridge a multi-screen experience. Guest author Peggy Allbright investigates the future of app development on companion screens -and TV apps in particular – and discusses how TV advertising has found a whole new screen to engage users on.