An anonymous reader writes Jake Wharton, Android Engineer at Square, has written an article about one of the big problems with building apps for Android: developers need a simulator for testing their software, rather than an emulator. He provides an interesting, technical explanation of the difference between them, and why the status quo is not working. Here are the basics of his article: "A simulator is a shim that sits between the Android operating system runtime and the computer's running operating system. It bridges the two into a single unit which behaves closely to how a real device or full emulator would at a fraction of the overhead. The most well known simulator to any Android developer is probably (and ironically) the one that iOS developers use from Apple. The iPhone and iPad simulators allow quick, easy, and lightweight execution of in-development apps. ... There always will be a need for a proper emulator for acceptance testing your application in an environment that behaves exactly like a device. For day-to-day development this is simply not needed. Developer productivity will rise dramatically and the simplicity through which testing can now be done will encourage their use and with any luck improve overall app quality. Android actually already has two simulators which are each powerful in different ways, but nowhere near powerful enough."