Connect camera to the Android phone via cable
There are a couple of phones that support USB host mode. You could check the compatibility list of the app "DSLR Controller" over here: http://dslrcontroller.com/devices.php

In the column "How to connect" are links to an adapter cable which enables you to connect a camera to your phone.

If your phone is listed there or you verify via outher sources that your phone supports USB host mode then you could try one of the cables listed there.

After that you would need an app that enables you to mount the camera storage so you can access it.

Today I ordered one of those cables and will try to connect a cardreader to my phone (Samsung Galaxy S GT-I9000). Will post further updates once the cable arrives.