Icenium itself is the IDE and cloud service and has not relevance to the performance of your app. You should check out general performance tips for speeding up apps that utilize web services. You might also consider profiling your app with the help of the Icenium simulator and its debugging tools to detect which part of your app takes most time. There are other good sources for performance tips out there e.g. Performance & UX Considerations For Successful PhoneGap Apps
Looking for tips & tricks directly from the Icenium team? Check out our blog!
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