The 4S has the usual features of an iPhone, plus a few things that are unique to the 4S.
For starters, the 4S functions very smoothly compared to its predecessors. Web browsing and multi-tasking have refined and are much more user-friendly. Battery life is also very important in this era of smart phones, and the 4S can last approximately two days without charge. This includes any browsing, calling, or music playing you may be doing in that time.
Now let’s get to that thing that makes this phone so different. Siri is a program that is connected to the internet and can be used to perform basic functions through speech. To activate it, you either hold the home button for three seconds, or hold the phone to your ear and speak.
So far, Siri has been everything that Apple said it would be. It can pull up the weather, tell the date and time, can set reminders, and even send text messages for you.
Siri is also capable of responding to certain phrases such as "Hello" or "How are you?" The only drawback is that to perform the previously stated functions, you need to use very specific commands and avoid phrases like, "Can you show me," or, "What is”, lest you activate a different command. This only slightly affects its usefulness and is likely to be improved in future updates.