Appium is not stable?

Hi All,

My testing environment is Windows 8.1, Appium, Android 4.3 tablet, Java 8.

I have implemented a bunch of test cases on Appium. It takes 30+ minutes to run all test cases.

But it looks like that the Appium is not stable, I may get different results if I run the test for times without changing anything.

Does anybody get the same problem?

Any help is appreciated.