A phone is a mobile device, I prefer to view my photos on a 30" calibrated S-IPS display. The PenTile Matrix technology used in the Galaxy S SAMOLED is very nice. The color temperature is high on it closer to 7500K, but serves it purpose quite well and pixelization is hard to tell. Utilizing the full resolution of the iPhone4 is somewhat difficult if you don't zoom in on a display. This is a personal choice. For a mobile device, I'll take something that has a bigger display, draws less current, but thinner and lighter weight.
That 30" calibrated S-IPS display is waisted on you if you think;
"The PenTile Matrix technology used in the Galaxy S SAMOLED is very nice."