Can I install Android on my non-Android device?
Is it possible to Port Android to Nokia 5230?
I would love to run Android OS on my Nokia.
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It might be possible. But you (I mean the royal "you", as in "a community of competent and dedicated developers") would need to write Android-specific drivers for every piece of hardware in that phone: CPU, RAM, screen, 2G/3G radios, flash storage controller(s), WLAN, bluetooth, etc.
Also, seeing how this particular handset's specs are very dated, even compared to the very first Android phone HTC Dream, a.k.a. T-Mobile G1 (434MHz ARM11 CPU Vs. 528MHz ARM6, 128MB RAM Vs. 192MB, 70MB internal memory Vs. 256MB) it might not be able to run any "modern" android version. Android 1.5, a.k.a. "Cupcake" might run on it (assuming it can fit into the measly ROM,) but it would most likely be very slow and unstable. You are probably better off sticking with SymbianOS 9 on your Nokia 5230 until you can upgrade to an official Android handset.