Lest you think that all we'll be spotlighting in this space is games, here's an interesting app meant for anyone thinking about adding a couch to that living room or putting an extra bed in the back bedroom. Home 3D is an "architecture and interior design app" that allows you to model out your home in 3D, including doors and windows on a floor plan, wallpaper, and furniture, allowing you to test out your choices on your device first before tearing out a wall or repainting a room.
Having all of this functionality on your iPhone or iPad is impressive (and the best home design software costs a lot more than this one -- US$3.99 for the iPhone and $4.99 for the iPad), but Home 3D does it with an impressive interface and a surprising number of features. You can use a color picker and choose from a set of pre-loaded furniture, buy more with in-app purchases, or try creating your own models or even using the iPhone's camera for textures.
It's not perfect -- if you want to do serious home design, you'll probably have to go for something a little more dedicated on the desktop. But just for moving some furniture around, or maybe seeing what a room might look like with a different color of paint, Home 3D does the trick.