As we tear our way through the iPad App Store, we've been focusing on iPad-specific versions of existing games. But for those who don't want to upgrade your existing library of games, the iPad does allow you to play those same games "pixel doubled". This simply means the entire game is scaled to fit the iPad's screen.
After spending some time with a few of these games, I've found the games are surprisingly playable. There have been no notable performance penalties for pixel-doubled games, though the scaled up graphics are noticeable. Realistic or detailed 3D graphics such as Real Racing and Dungeon Hunter suffer the most, vs. more cartoon themed games like Soosiz. You will find, however, that in many cases developers have moved controllers slightly in order to accommodate the iPad's larger screen size. This can be see in Soosiz and Dungeon Hunter below.
Here are pairs of side-by-side screens for a few iPad specific games and their pixel doubled iPhone counterparts. Click to see full-size images. Pixel doubled on left, iPad-specific on right:
Here's an attempt at capturing the two in video:
Unfortunately, it doesn't show very well in a YouTube video. While the iPhone version is perfectly playable, the experience is much nicer on the iPad version.
After having played all these versions side-by-side, it's clear if you're an iPad owner, you are going to want to play your games in native mode when possible. Pixel-doubling is a nice way to keep your previously-played library accessible, but for new games HD-versions feel so much better. How can you tell which old games are worth upgrading? Stay tuned, we're working on a guide for that.