That doesn't bother me so much, because if Sherlock were a modern figure, he'd carry some kind of mobile device and use it the way he does in the show. There isn't a lot of pomp and cirucmstance made about him unlocking his phone and carefully navigating the nanometer-engineered laser-etched icon menus, isn't this device amazing, you should buy one. You near a text message notification (which many of us hear, from our own devices, or our neighbors', on a daily basis), he looks at the phone, the shot shows the phone, and highlights the contents of the message as a storytelling device, rather than as an advertisement for how pretty Apple's software is.
I'd like to clarify that I'm not an Apple fanboy by any means - my mobile devices are all Android, and I primarily work on Windows machines. I don't have any issue with characters using modern technologies as part of a story, but when the storytelling detours for the sole purpose of advertising a product, it gets wonky.
Some more of my favorite examples:
Nissan/Fringe - http://www.youtube.com/watch?v=s4fY1_NSxF0
Windows Phone/Castle - http://www.youtube.com/watch?v=DFPcvcTzdYY
Hyundai/Burn Notice - http://www.youtube.com/watch?v=A4xlSN9_XT0
Subway/Hawaii-50 - http://www.youtube.com/watch?v=oQYwFND7rHE
On the flip side, Chuck did Subway's product placement very well - they just leaned into it and played it for laughs, rather than trying to oh-so-cleverly have Serious Characters eat Serious Lunch with Serious Nutritional Value. The show just owned the fact that Subway had shoved a crackload of cash at them and went overboard with it.
http://www.youtube.com/watch?v=wdaHx0_PmC0