[android] Listing all extras of an Intent

If for debugging all you want is a string (sort of implied by the OP but not explicitly stated), simply use toString on the extras Bundle:

intent.getExtras().toString()

It returns a string such as:

Bundle[{key1=value1, key2=value2, key3=value3}]

Documentation: Bundle.toString() (it's unfortunately the default Object.toString() javadoc and as such quite useless here.)