iPhone has a great operating system upgrade strategy. Unlike Android, which does not support all smartphone brands and different hardware configurations, Apple takes care of its products and releases the iOS updates across all its hardware. However, hardware limitations restrict older hardware from its updates.
The last update we saw was the iOS 7, which was available for the iPhone 4 and 4S too, but while the iPhone 4S sports a supporting hardware, the iPhone 4 had serious compromises.
The new iOS 8 update is available for all Apple products sold since 2011. These include iPhone 4S and above, iPad 2 and above and the iTouch 5.
The iPhone 4S will get the iOS 8 update. However, it will also see a few issues along with it.
According to an article on Ars Tecnica, the iPhone 4S will face issues on the new iOS 8 operating system. The iPhone 4S will see a few missing features, such as AirDrop, TouchID, Handoff for applications and support for OpenGL ES 3.0, Metal Graphics API and 64-bit ARMv8 apps.
Not only will there be a compromise on features, it will also have issues with performance. Lacking a 64-bit architecture, the iPhone will run slower than before. The display being smaller (3.5-inches), you would also suffer with screen realty in a few apps.
Ars Technica also has noticed that apps respond with longer time on iOS 8 in contrast to iOS 7. They tested a few apps and the time they take to start. For example, Safari takes 1.25 seconds on iOS 7 and 2.16 seconds on iOS 8. The camera starts up in 1.5 seconds and 1.8 seconds respectively. Clicking on the settings, icon took 1.25 seconds on iOS 8 in contrast to 0.95 seconds on iOS 7. These are examples, which show the sluggish behaviour on the iPhone 4S. Though these may not be huge differences, they can get a little frustrating since you would have been used to a faster, smoother experience, on the same handset, before.
However, the main question is ‘should you upgrade?’ we would suggest to go ahead and do it. The minor slowdown would not be worth enough for losing out on new features of the iOS 8. To play safer, we suggest you wait for an iOS 8.0.1 or an iOS 8.1 update so that the problems of older devices would be addressed, and the issues ironed out.