We know Apple doesn't dwell on technical details when talking to the public, but with developers they're more willing to talk product specs.
MacRumors first reported the news after Apple uploaded videos from each of the sessions Thursday.
This detail is notable because it means the iPhone 4 has twice the RAM of the last iPhone, the 3GS, and twice that of the iPad, which launched less than three months ago. Both have 256MB of RAM.
The bump in extra memory makes sense since this iPhone is the first to support, one of the biggest new features of iOS 4, which . The new iPhone 4 hits stores on June 24.