The iTunes App Store offers a selection of photography apps for iPhone, iPod touch, and iPad for free. Each is between $1 and $2 off. The apps:

• PhotoFusion for iPhone and iPod touch (pictured, $2 off): Photo editing app
• LensLight for iPhone, iPod touch, and iPad ($2 off): Lighting effects app
• Vintage Camera Pro for iPhone, iPod touch, and iPad ($1 off): Add vintage filters to your photos