At a Glance: The iPhone 4S vs. older iPhones

Apple unveiled a faster, more powerful iPhone on Tuesday called the iPhone 4S. It's not the radical update -the iPhone 5 - that some people had expected. The 4S will be available on October 14. Consumers can begin pre-ordering the new device beginning on Friday.

Based on details the company provided, the new iPhone is still an upgrade from previous versions. Here's a look at the key differences between the iPhone 4S, the iPhone 4 and the 3GS.

iPhone 4S tech specs:

- Capacity: 16 gigabyte model for $199, 32 gigabytes for $299 and 64 gigabytes for $399

- Size: height: 4.5 inches; width: 2.31 inches; depth: 0.37 inch (the same as the iPhone 4)

- Weight: 4.9 ounces

- Display: retina display, 3.5-inch (diagonal) widescreen multi-touch display

- 8-megapixel camera

- Video recording: high-definition (1080p - comparable to the resolution of a 40-inch flat panel TV) up to 30 frames per second with audio

- Battery: talk time is up to 8 hours on 3G, up to 14 hours on 2G. Internet works for up to p to 6 hours on 3G, and up to 9 hours on Wi-Fi, one hour shorter than the iPhone 4. Up to 10 hours of video playback.

- Dual-core A5 processor (which is twice as fast, and renders graphics 7 times faster than the previous model's A4 processor)

- Video calling: Facetime

- Wireless carriers: AT&T, Verizon Wireless and Sprint Nextel

-Release date: October 14, 2011

iPhone 4 tech specs:

- Capacity: 8 gigabyte flash drive (Apple is no longer selling the bigger versions)

- Size: height: 4.5 inches; width: 2.31 inches; depth: 0.37 inch

- Weight: 4.8 ounces

- Display: retina display, 3.5-inch (diagonal) widescreen multi-touch display

- 5-megapixel still camera

- Video recording: high-definition (720p - comparable to an older-model flat panel TV) up to 30 frames per second with audio

- Battery: talk time is up to 7 hours on 3G and up to 14 hours on 2G. Internet works for up to 6 hours on 3G and up to 10 hours on Wi-Fi. Up to 10 hours of video playback.

- Video calling: Facetime

- Less powerful A4 processor, not dual core

- Price: $99 with a two-year contract

- Wireless carriers: AT&T, Verizon Wireless

-Release date: June 24, 2010

iPhone 3GS tech specs:

- Capacity: 8 gigabyte flash drive

- Size: height: 4.5 inches; width: 2.4 inches; depth: 0.48 inch

- Weight: 4.8 ounces

- Display: 3.5-inch (diagonal) widescreen multi-touch display.

- 3-megapixel camera

- Video recording: up to 30 frames per second with audio, no HD