Should I use the bouncy castle libraries or the ones included in Android for AES

I'm writing an android app where I need to use AES. Is it better to use the bouncy castle libraries or should I just stick w开发者_开发问答ith what is included in default android libraries?

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I think the question might be phrased better the other way - why would you not use the built in libraries?

Anyway, here's a helpful link with some code samples: Encryption compatible between Android and C#