Users could do things with the fifth-generation iPod that they could only dream of with the fourth-generation version of the device. The fifth-generation iPod's ability to display video and pictures stored on the device was a key difference from its predecessor. The fifth-generation iPod also featured a color screen, longer battery life and much more.
Hard Drive and Battery
Fourth-generation iPods offer either 20, 30, 40 or 60 GB of storage space; buyers could choose among 30, 60 or 80 GB of storage capacity with the fifth-generation iPod. The battery for each generation takes four hours to charge, but the fourth-generation iPod only offers 12 hours of playback on a full battery while the fifth-generation model provides14 hours of playback.
Video and Color
Users can enjoy video playback and the ability to display images with a fifth-generation iPod, an option not included with the fourth-generation device. MPEG-4 is the only video format that can be played on the fifth-generation iPod, and JPEG, BMP, GIF, TIFF, PSD and PNG are the only image file formats the device can display. The fifth-generation iPod also comes standard with a color screen; only the third iteration of the fourth-generation iPod offers a color screen.
USB and FireWire
The fourth-generation iPod let users charge and sync their device using either USB or FireWire cable, both of which came with the iPod. While the fifth-generation iPod has inputs for both USB and FireWire, FireWire can only be used to charge the device; USB is the only way to both sync and charge the device.
The fifth-generation iPod features a larger screen, mostly to accommodate the video and image-viewing features. The fifth-generation device has a screen that measures 2.5 inches diagonally; the fourth-generation iPod screen only measures 2 inches diagonally. The fifth-generation device also boasts a 320-by-240 resolution compared to the 160-by-120 resolution on the fourth-generation iPod.
Supported Audio Formats
The fifth-generation iPod builds on the audio formats supported by the fourth-generation model. The fourth-generation device supports AAC, MP3, AIFF and WAV audio formats; the fifth-generation adds Apple Lossless and Audible (AA) audio formats to that list.