The Nokia N91 is a smartphone produced by Nokia as part of their Nseries line of portable devices. It was announced on April 27, 2005 along with N70 and N90 as the first three Nseries devices. The N91 ran on Symbian-based S60 3rd Edition (the first to run on Symbian 9.1). It was the first ever phone encompassing a 4 GB internal hard drive, allowing storage for 3,000 songs (an 8 GB revision came later). The N91 is highly focused on music. with dedicated music keys on the front which slide down to reveal the keypad. It also featured the industry-standard 3.5 mm headphone jack, and was anticipated as a major challenger to Apple, whose iPod dominated the industry. The design of the N91 is based on stainless steel with a matte finish.