I hear the Chinese system of logograms is extremely difficult to use; that Chinese kids take a lot longer to master writing than their European counterparts.
Korea developed the Hangul script, which is said to be one of the simplest and most logical phonetic scripts in the world. Why hasn't China done the same? I hear they've developed a few, like Bopomofo and pinyin, but they don't see regular use outside of academia.
Pinyin is actually widely used by pretty much anyone who uses the internet in China (which is, as you can probably imagine, a LOT of people).
As you may know, Chinese people generally have keyboards that very closely resemble keyboards you could find in America or Europe with alphanumeric keys.
To type in Chinese, they must know and enter the pinyin of the words they want.
So the answer to your question is, China pretty much has a phonetic system of representing their words.
It's simply used as a medium to 'call' the characters they want.
Chinese speakers/writers are generally pretty comfortable using only pinyin when using apps/programs/games/etc when displaying actual Chinese characters is not supported.
Finally, this system of calling Chinese characters is not unique to Chinese, as this is largely how Japanese people type on devices as well (note that Japanese has a large number of Chinese characters incorporated into their language known as kanji)