Espresso is faster than robotium

Espresso and Robotium are instrumentation-based frameworks, meaning they use Android Instrumentation to inspect and interact with Activities under test. The major advances in Espresso over Robotium:    

1.Synchronization: By default, instrumentation test logic runs on a different (instrumentation) thread than UI operations (processed on the UI thread). Without synchronization of test operations with UI updates, the tests will be prone to flakiness - i.e. will fail randomly because of timing issues. Espresso takes care of thread safety by seamlessly synchronizing test actions and assertions with the UI of the application under test. Robotium attempts to address this with sleep/retry mechanisms, which are not only unreliable, but also cause tests to run slower than necessary.

2.API: Espresso has a small, well-defined and predictable API, which is open to customization. 

3.Clear failure information: Espresso strives to provide rich debugging information when a failure happens. Further, you can customize the way failures are handled by Espresso with your own failure handler. 

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