ES2RTTexture.readPixels():
This method could use the pixels buffer directly if it is a ByteBuffer. It would still have to run through and reverse the B's and R's, but it would save on an extra allocation.

And possibly even in the int buffer case - can GL read into an int buffer as well? Again, the bytes would still have to be swapped and that case would probably have to deal with endian issues, but it would save the allocation...