For cleaning windows, I recommend 'degreasing' them. That's mostly what causes the streaks. Be it inside or out.
Best way to get rid of it is get some hair shampoo, and wash the windows with it. THEN, dry them with newspaper. You won't even need to use any type of glass cleaner.
Roger, DO NOT CLEAN/DRY windows in the sun. Don't even do the above in the sun. Streaks dry much quicker in the sun (duh). Do it in the shade, then make sure you don't leave any streaks by getting a REALLY dry towel/newspaper and wiping everything off.
Just telling what works from experience....
John
