Many top-performing apps are still lacking in the areas of usability and performance, according to research by the App Quality Alliance (AQuA).

Although the body found apps such as Angry Birds, Facebook, YouTube, Asphalt and Cut the Rope had high overall quality, they still had areas which could be improved.

In terms of usability, each of the top apps tested had at least one significant issue, and three had critical issues that caused crashes.

In terms of performance, battery life improvements of up to 19 percent could be achieved by top apps if the timing of data requests was better optimised.

In addition, the amount of data transferred could be cut by up to 18 percent by reducing the duplication of data being passed to mobile devices.

One way in which this could be done is through the use of caching instead of downloading thumbnail images.

AQuA tested the top apps from the likes of Gameloft, Facebook, Rovio, Google, Swiftkey, Electronic Arts and Zeptolabs against industry testing criteria and using AT&T’s Application Resource Optimizer (ARO).

It found that the top 10 reasons for apps failing testing are UI inconsistency; lack of clarity in graphics and text; app browsing confusion; language inconsistency and spelling errors; privacy policy omission; hidden features; apps crashing; a lack of help option; lack of notification about network connection; and screen orientation distortion.

AQuA is a non-profit organisation for supporting quality app development with members that include AT&T, LG, Motorola, Nokia, Oracle, Orange, Samsung and Sony Mobile.