Just a week earlier, HTC said it would spend $18.5 million to buy Dashwire, which sells a technology that lets users back up photos, contacts, text messages and other smartphone data in the cloud, and to access that data from a PC Web browser. HTC said it will integrate the service with HTC Sense, its user interface for Android phones.

HTC's competitors are also building cloud services -- notably Apple's iCloud storage service, unveiled in June. They are also using other weapons, including technology patents. In March last year, Apple sued HTC for alleged infringement of 20 patents related to the iPhone's user interface, hardware and "underlying architecture."

HTC seemed caught off-guard by the lawsuit, which some analysts have said could eventually require it to pay royalties to Apple. But HTC has shot back with lawsuits of its own, and this year it turned to another acquisition for help.

In July HTC said it would buy graphics chip maker S3 Graphics from Via Technologies for US$300 million. HTC will get S3's portfolio of 235 patents and pending applications, including many related to graphics.

It was perhaps no coincidence that a few days before the deal was announced, an ITC judge ruled that Apple had infringed some of S3's patents.