BEIJING (Reuters) – China Mobile Ltd, the worlds largest carrier by subscribers, missed estimates for 2013 with its first annual profit drop in 14 years as messaging services like Tencent Holdings WeChat continued to replace formerly lucrative SMS usage. The companys net profit fell 5.9 percent to 121.8 billion yuan ($19.66 billion) last year, missing analyst estimates of 125 billion yuan, according to a Thomson Reuters Starmine survey of 31 analysts. Revenue for 2013 rose 8.3 percent to 630.2 billion yuan. China Mobile shares were down 1.9 percent on Thursday morning, versus a 1. …