No one could have predicted how popular Siri would turn out to be. After all, voice-recognition apps are nothing new. While initial skepticism over the new iPhone 4S’s technical specifications compared to the previous model had some wondering if the device would be a dud for the company, the smartphone has been a runaway success. Apple (NASDAQ:AAPL) sold 4 million iPhone 4Ses in just three days, and the device continues to do brisk business thanks to the novelty of Siri.
But now, as more people are figuring out Siri’s numerous uses, the program is increasingly proving to be a threat — and not just to other voice-recognition apps. The digital assistant is muscling in on multiple territories of the technology business. Here’s a look at some of the biggest businesses and products that should be worried about Apple’s new toy: