英文小問題 有關making sentences

Although “in spite of” is perfectly standard English, some people prefer “despite” because it is shorter. Be careful not to mix the two together by saying “despite of” except as part of the phrase “in despite of” meaning “in defiance of.”
And note that unlike “despite,” “in spite” should always be spelled as two separate words.
http://wsu.edu/~brians/errors/inspite.html
Despite mobile phone cost is high, it is a convenient tool.
Mobile phone can be a convenient tool despite the costs.
Mobile phone can be a convenient tool in spite of the costs.

*** I'm not sure whether u are refering to the mobile cost itself or the calling charges.. well,.. Hope that I hv answered your requests properly. Cheers!

2008-06-09 02:54:50 補充：
Be careful >>> "in defiance of " ==> 無視; 違抗
So, ... don't use DESPITE OF... unless, u'd need such meaning for particular uses.
==> in defiance of ===> in contempt of, in opposition to, in disobedience to