Which iPhone was the most upgraded compared to the previous model?

[irDigital0l]

So which iPhone had the most upgrades compared to the previous model? So its iPhone 3G compared to the original iPhone, iPhone 3GS compared to the iPhone 3G, etc.

I quickly made a list of some key features (yes this isn't the full list).

iPhone 3G
- 3G
- GPS
- Accelerometer
- flush headphone jack

iPhone 3GS
- Voice Control
- Faster processor
- 7.2 HSDPA
- 3MP camera with 480p video
- Magnetometer and Compass

iPhone 4
- All-new design
- Retina display
- A4 chip
- Gyroscope
- 5MP camera with LED flash
- 720p HD video recording
- FaceTime
- Verizon & Sprint

iPhone 4S
- Siri
- A5 chip
- 8MP iSight camera
- 1080p HD video recording
- HSPA+ and World phone
- AirPlay Mirroring
- Bluetooth 4.0
- 64GB storage

iPhone 5
- Thinnest & lightest design
- 4-inch Retina display
- 4G LTE
- A6 chip
- FaceTime HD camera with 720p HD video
- Enhanced audio
- Lightening connector

I have to say that the iPhone 4 shows the biggest improvement compared to the iPhone 3GS. iPhone 4 introduced Retina display, Apple's own A4 chip, FaceTime, 5MP camera with 720p HD video, and more carrier options.

Would like to hear other opinions.

 

[ECUpirate44]

Agreed, iPhone 4.

 

[zhandri]

4 was huge. the retina and the new design. design won't change that much in the near future. it looks like apple really is very satisfied with that way the iphone looks right now

 

[Big.Mac.Daddy]

Retina screen has been the biggest impact of any improvement so far.

iPhone 4 for me too.

 

[hawk1410]

iPhone 4 obviously, not only the design changes but many new hardware features, like the retina display. And Apple finally added a front facing camera and a semi decent back camera for pics with a flash. iOS4 itself was a pretty big change, inclusion of proper multi tasking etc etc. Dont think apple can top the Phone 4 launch