Leaders across most industries prioritize mobility for both their workforce and consumers. Implementing successful mobile app development is challenging, involving performance and quality optimization on top of development of app functionality. Slow, bug-riddled apps will negatively affect return on investment and also harm your company’s reputation.

Sure, there’s a “cool factor” to many great apps, but users mostly just want them to work properly. Mobile app development begins with knowing your target audience through usability studies and group testing so you can define your objectives clearly.

The “backend” of mobile app development has to be tailored to users’ particular needs. Apps may look simple, and they may be designed to do simple things, but there’s plenty of complexity within their supporting infrastructure. Support for your mobile app, including performance monitoring, tuning and bug fixes, are also critical to successful mobile app development.

Great ‘Apps’ Expectations

From 2011 to 2012, the average mobile user went from having 32 apps on their mobile device to having 41, according to Nielsen research. An overwhelming majority of smartphone users (85 percent) prefer mobile apps over mobile websites because they’re more convenient, faster and easier to browse.

Most importantly, app users don’t put up with problems. Seventy-nine percent of app users in a Compuware survey reported they would only give an app one or two more chances if it didn’t work on the first try (Source: TechCrunch). Only 16 percent said they would give an app more than two attempts.

The most common performance issues annoying app users are crashing, lagging, and sluggish load times — these factors account for around half of all poor reviews on app stores (Source: Information Week). Appfigures, a reporting platform for mobile developers, analyzed 25 million English-language app reviews and found that in one-star reviews, the most frequently used words (“work,” “time,” “fix”) referred to poor performance. By contrast, five-star reviews tended to focus on user experience, with descriptors like “easy,” “great” and “fun.”

Critical Mobile App Development Factors

Getting four and five star reviews right out of the gate can determine whether your company’s mobile app soars or sinks into oblivion. And if you want the best shot at great mobile app reviews, you cannot ignore app testing.

Thorough functionality testing should be a priority from the very beginning of mobile app development. But functionality testing is just the beginning. Developers should also examine things like audio and video playback, script and library compatibility, and calculations performed by the app.

Mobile app development testing should include provision by your app developer of diagnostic logs including crash reports, CPU usage and power consumption. Users expect their apps to work correctly, quickly and consistently, starting from the first use. To please users, you need to test every component of your app that helps the user achieve any type of result, from calculations to the display of content.

User Interface and Usability

User interface and usability are critical to successful mobile app development, and that means you have to thoroughly test app navigation, help features, cross-browser compatibility, error messages and general program layout. A quality front-end experience for users is the key to getting those great reviews that keep your app high on the list of popular downloads.

Your mobile app development team has to test their programs under the conditions that users actually experience. Does your app developer have a mobile app testing platform that gives them realistic test environments, real-time analytics and the data they need to not only solve problems, but make use of the app a hassle-free experience? They should.

The Difference a Star Can Make

App store ranking has an exponential correlation with sales, accounted for by recommendations from one user to another and from coverage on app review sites. Conversely, an increase in app performance problems and response times correlates to a drop-off in user adoption.

According to Appurify, with app store reviews, an app with a 4.5-star review will be downloaded nearly four times more than an app with a 3.5-star review. Only comprehensive testing of functionality and user experience can reliably make the difference in how well an app is appreciated by users.

In conclusion, your mobile app development team should bring extensive software and mobile app development experience to the table, and should be willing to develop a cost-effective solution and work towards a fruitful and long-lasting collaboration.

Andrew Sosa is co-founder of SquareBall Studios (SBS), a leading development company of mobile applications and software systems. Andrew has helped develop solutions for Fortune 500 companies but his real passion is working with startups on their initial ideas and seeing them succeed. This article originally appeared on the Squareball Studios blog.