首先，对同一个名词，同时用不定式和定语从句是没有任何问题，关键在于如何表达。
就该例句而言，先说明陈述其两面性，后简单总结即有前因后果之意。不过在结构上和用词上不太准确，如 a tool to lead to ……and that……的结构就不太好，常见用法：tool of sth, tool for sth/doing sth （参见麦克米兰英语词典）,并不适合跟从句。就例句而言，可以考虑这样写：Cell phone has also two aspects good and bad, by it to play mobile games comes to a majority of youth's liking, especially students who's lacking self-restraint.