iPhone

Well, If you don't have an iPhone, you don't have an iPhone. Apple was true to its word on iPhone's Ad. Since the Launch of the first iPhone on 2007. Apple has changed everything. Everyone started to follow iPhone and everyone tried to Outsell iPhone but no one ever could. Everyone added what was missing on iPhone. But still iPhone is one of the top selling phones in the market. 

iPhone is a line of internet and multimedia-enabled smart phones designed and marketed by Apple. As shown in the figure the time line for iPhone was 2G on 2007, 3g on 2008, 3gs on 2009 and the latest iPhone, iPhone 4 on 2010. The new version of iPhone, iPhone 5 is expected to be released in 2011, along with the iOS 5.  

     iPhone enables you to shoot Video(from iPhone 3gs), take photos, it is a portable multimedia player, web browser over WiFi and 3g, can send texts ,receive and give phone calls, Video calls over WiFi too on iPhone 4, receive and send voice mails and much more. You can download and play games and use apps right from your phone, purchase and listen to music, watch movies, podcasts and so on. It's an Smartphone that is suitable for everyone. 


iPhone has four generations and all 4 are better that their previous model. The models are 
:-


iPhone 2G

The first iPhone. After the big hit of the iPods Apple launched their first touch screen controlled phone. Which runs on 2g networks, was available on 4GB, 8GB, and 16GB models, operates on iOS and WLAN for internet. This phone revolutionized the new era of smartphones. Every other companies started following the iPhone and started to add functions that were missing on the iPhone 2G. Still iPhone alone was ahead of them all. And slowly when 3g network was established. Apple Launched iPhone 3G.




iPhone 3G
After the new era of 3G Network was released.iPhone 3G was released for faster and Advanced networking. This iPhone could run 3rd Party applications and was way to fast than the original iPhone. Camera was improved , but we still couldn't take videos. This iPhone was available on 8GB and 16GB Model. And was much more thinner than the original iPhone. it had the same WiFi and Bluetooth for connectivity and was also portable media player like iPhone 2g. But this one had the better battery life that the 1st iPhone. This phone even included GPS too. After this iPhone the Applications for iPhone was introduced. 




iPhone 3GS 

When iPhone 3g went a big hit and every other companies like Nokia, Samsung etc. started to compete with iPhones, . Apple again launched iPhone 3GS, S for speed. As this phone is twice as fast than the iPhone 3G. And Slimmer than the 3G. It can do everything the iPhone 3G could do and much more, but twice as fast. This iPhone can record videos too, on 480p the videos taken on this device looks amazing. And the camera was improved from 2MP to 3MP. After launching iPhone4 Multitasking came to this device too and from then we can run our  applications on the background and get back to them whenever possible. This iPhone was available on 8GB, 16 GB and 32 GB model. However, Apple is only shipping 8GB model now. 


iPhone 4

The Biggest leap since the original iPhone. After the big hit of iPhone 3G and iPhone 3GS on 2010 Apple introduced the new iPhone 4.  While everyone else was busy trying to keep up with iPhone, Apple was busy creating amazing new features that made iPhone more powerful, easier to use, and more indispensable than ever. The result was iPhone 4. The biggest thing to happen to iPhone since iPhone. Every Single thing was improved. The changes and the features of the iPhone 4 are:-

Facetime

 

Facetime was introduced along with the iPhone 4 which changed the way we communicate. Facetime enables us to make Videocalls from iPhone 4 to Other iPod Touches, Macs and iPads over WiFi.Don't just say hello smile at someone when you call them. This feature brought Phone calls into reality

Retina Display

 

The Retina display on iPhone 4 is the sharpest, most vibrant, highest-resolution phone screen ever, with four times the pixel count of previous iPhone models. In fact, the pixel density is so high that the human eye is unable to distinguish individual pixels. Which makes text amazingly crisp and images stunningly sharp. And the retina display in the iPhone makes web page, apps and Games look amazing.

Multitasking

iPhone 4 introduces a whole new way of multitasking. Now you can run your favorite third-party apps — and switch between them instantly — without slowing down the performance of the foreground app or draining the battery unnecessarily. This smarter approach to multitasking is available only in iOS 4, which is also for the iPhone 3GS. Multitasking enables you to run all your favorite apps on your background ans get back to them whenever you want.

HD Video Recording and editing

Shoot your own movies in high definition. Capture impressive video even in low-light settings, thanks to the advanced backside illumination sensor and built-in LED light. Then edit and create your own mini-masterpiece right on iPhone 4 using the iMovie app — with Apple-designed themes, titles, and transitions. It’s available on the App Store. With full 780p HD video recording you can now shoot and edit your own Movie. And upload them on other video channels like you tube or share them on facebook or twitter.

5 Megapixel Camera with LED Flash

Shoot your own movies in high definition. Capture impressive video even in low-light settings, thanks to the advanced backside illumination sensor and built-in LED light. Then edit and create your own mini-masterpiece right on iPhone 4 using the iMovie app — with Apple-designed themes, titles, and transitions. It’s available on the App Store. with 5 megapixel and retina display, Pictures Taken From the iPhone 4 look Amazing.

   

And Over 200 New features are added to the new iPhone 4. These are the main changes.