Do any of the Android-based wallets support cold storage? Specifically I'm looking for Armory-like functionality where the transaction can be generated on an online system, transported to an offline android tablet or netbook via USB or QR code where it can be signed, then transported back to an online system where it can be broadcast.
Its not exactly what you want, http://mycelium.com/ for Android does it the other way around.

You keep your private keys safe in QR-code format on a paper or a offline device, then you scan it when you want to make a transaction. Mycelium signs the transaction and forgets about the key.

I tried to scan with my Android device offline, but it does not work. To be able to select previous outputs to send in the transaction, you need to be online.

I don't know of any Android app that can take a raw transaction (by QR-code, SD-card, OTG, Bluetooth, NFC or Chirp.io) and sign it offline. 

I hope this feature will be implemented soon.