Under the covers, part 2: Memory, storage. Nexus One has 512MB FLASH and 512MB of RAM onboard, to support lots of multi-tasking apps, and impressing many reviewers with its speed. iPhone 3GS has 256MB RAM. A removable SD card gives Nexus One 4GB of storage (expandable to 32GB). But according to Walter Mossberg, Google only allows 190MB of all that to store apps. By contrast, nearly all of the 16G and 32GB on the iPhone flash drives is user-accessible.