In the current digital product market, the tablet computer is the most popular digital product. With its outstanding portability and smooth running, it has been recognized by many people. Apple iPad, Lenovo Lepad ,Acer A500 W500, Motorola MOOX and BlackBerry PlayBook are relatively popular in the tablet computer market. These tablet computers are depending on the outstanding performance of configuration and the powerful feature function, which makes them occupy a space in the market. The tablet computer is the same as an ordinary computer, which is made up of hardware and software system. Hardware is equivalent to the human body and software features are similar to the human brain. For the tablet computer, the reasonable combination of operating system and hardware is very important. What is more, the manipulation of experience is the most critical factors for the tablet computer. Current involved tablet computer operating system mainly includes iOS, Android, Windows, BlackBerry Tablet OS and so on. However, taking a panoramic view of the market, their system each has good points, each has inadequacy. The iOS system proudly ranks top in market share, Android has a powerful brand camp. The Windows-based tablet computer operating system is strengthened to the compatability with desktop applications. BlackBerry Tablet OS is more interested in business application. Now today, I will briefly introduce the advantages and disadvantages of Apple iOS. Apple iOS, formerly known as iPhone OS, it is used mainly in iPhone, iPod touch and the iPad. It also has the same UNIX structure origin as Apple's Mac OS X operating system. The iOS is touting three versions for iPhone, iPod Touch and iPad, but the three versions are always synchronized to upgrade and evolution. The latest version of iOS is iOS 4.3.5 version, which was launched in July 26, 2011. Advantages: Apple iPad and ipad2 are currently equipped with iOS system, which are the most successful products. It has more than 300,000 online applications , which is incomparable with other tablet computer systems. Apple's perfect culture made ipad a fashion art. What is more, system optimization is very much in place, even may say that is the smoothest system in the current computer industry. Disadvantages: its biggest drawback is that it is a completely closed system. Although the iOS application is very large, all of them are made by professional staff, so it can be said that we have to buy all the software (some of the features can be cracked.).For the intrinsic limitation of the iOS, a lot of third-party applications can not be installed, even JAVA is not running (JAVA can be used for all platform.).What is worse, many users use ipad to surf the web, but it does not support many common video formats, such as flash, avi, flv, rm and so on. Even we can not copy dvd to ipad, we have to use a dvd to ipad converter like this to help us to rip and copy dvd to iPad H.264, MPEG-4 videos in different resolutions. This paper states the advantages and disadvantages of iOS system, we can draw a conclusion that there isn't a flawless and perfect thing in the world, so ipad is not perfect either.