Question: What are the free testing tools for android and iOS mobile application?

Answer: 
Seetest is a one more testing tool. You can download its trial version. Why I suggest this to use over robotium is because of its platform independence. Just write a test script for android and run the same script across all the other platforms like Windows Phone, IPhone, Blackberry, Symbian.
Here is the link to download its trial version.
<http://experitest.com/support/download-2/>

Thanks,
Sangram
Android has the [Monkey](http://developer.android.com/guide/developing/tools/monkey.html).