Apple iOS 5 is not intended only for the company’s fresh products. The operating system will run on the most recent versions of iPhones. You can install and run iOS 5 on the previous iPhone 4, the most circulated iPhone version ever. If you don’t wish to spend extra bucks on the new iPhone 4S or if you think iPhone 4S does not worth your money, you can better get iOS 5 installed on your current model, iPhone 4. But sadly, all features of the feature-rich iOS 5 will not work on iPhone 4. You will miss some important features; however most features will run on the device. Go through the article to see which key features of iOS 5 will be there on iPhone 5 and which are not.

Features you'll relish on iPhone 4
1. iCloud
Apple’s much-coveted cloud based media service dubbed iCloud will work on iPhone 4 if you install iOS 5 on the device. iCloud is Apple’s new landmark product that will push the data from your device to the cloud automatically. You have to do nothing to transfer the data including images, texts, bookmarks, and contacts to the cloud servers of Apple. It will happen quite automatically if you activate the service. The result of the feature is that you will be able to access your valuable data from any iDevice and Mac computers from anywhere in the world.
2. iTunes Match
iTunes Match is Apple’s music service in reply to Amazon’s Cloud Drive and Google’s Music Beta. The feature is actually part of Apple iCloud. You can sync your iTunes purchased songs with ten other devices quite instantly with iTunes Match. But the feature lacks streaming capability like Cloud Drive and Music Beta. It is only an application to manage the music on iCloud, which you purchase from iTunes.
3. Photo Editing
Apple iOS 5 is up with Adobe Photoshop Express, a complete one-touch photo editing software. After capturing a still image on your iPhone’s camera, you can crop, adjust color and contrast and rotate the image with Adobe Photoshop Express. Instant editing brings you an attractive image that you can share with your friends on Facebook or other social media sites.
4. iMessage
iMessage is iOS 5’s one of much-touted features. In his keynote address at WWDC 2011, the former Apple CEO Steve Jobs specially noted the feature. It is proposed to let you send free messages between iDevices via Wi-Fi or 3G. You will be able to send text, image, animation and video messages in a matter of time. Group messaging and composing of message will be simple tasks on your device with iOS 5.
5. Twitter
Apple iOS 5 is with an astonishing Twitter integration. If you are not a Twitter user, iOS 5 will certainly encourage you to join the micro-blogging site. With iOS 5, all important apps of your iPhone like Safari, Maps, camera and many others will have Twitter integration. You can straight away tweet from the application you are with on your iPhone.
Features you'll miss
1. Siri
Siri is iPhone 4S’ celebrated voice recognition feature. You will be able to talk to your iPhone instead of typing text messages and search keywords with Siri voice recognition feature. But it works on iPhone 4S because of its high performing dual core A5 processor. It means iOS 5’s much-touted voice feature will not work on iPhone 4 that has Apple’s single core A4 processor. Of course, you will miss the much-excited iOS 5 feature on your iPhone 4.
2. AirPlay Mirroring
AirPlay Mirroring is yet another largely-appreciated feature of iOS 5. It lets iPhone users view the contents of their handset on large screens like HDTVs and Apple TVs wirelessly. You can watch movies, surf the web and play games on the large screen instead of iPhone’s crammed 3.5-inch display. This feature will not be on iPhone 4 even if you run iOS 5 on it.