In addition to being big and fast, the Xperia Z Ultra performs two really neat tricks. The first is that it's waterproof. No, I don't mean it's splash resistant. You can literally jump in a swimming pool with it and take pictures and videos underwater. (It's not for deep-sea diving. Sony recommends a maximum of five feet deep for a maximum of 30 minutes.)
The second neat trick is that you can use just about anything as a stylus, including a regular No. 2 pencil.
Such a giant phone is great when you're watching a movie, reading an e-book, playing a game or doing other things normally associated with tablets.
The trouble is: What happens when the phone rings? Do you pull this huge device out of your backpack or purse and hold it up to the side of your head?
Sony's wearable 'phablet' accessory
What happens when you want to check who's calling, check a social media notification alert, send a short text message, look up a quick Google Now query or do any number of the actions we all obsessively do all day with our phones.
Taking out a 6.4-in. screen device is a bigger deal than pulling out a phone. And that's one of the problems with "phablets."
Sony also announced this week a really unusual Bluetooth peripheral device designed to work with "phablets." It's called the Sony Smart Bluetooth Handset SBH52.
When the phone rings, you answer it like it's a phone by holding it up to your ear. Or, you plug your earbuds into it like you would a regular phone. The difference is that it's a tiny fraction of the size of even the smallest smartphone.
It's also different because you pair it with the Xperia Z Ultra by simply tapping it against the phone. They both support NFC.
The Smart Bluetooth Handset SBH52 is basically a controller that clips onto your shirt or anything else and enables you to monitor and control audio beamed wirelessly from a phone or "phablet."
It's got a low-resolution screen to display the time, text messages, caller ID information or the current track. It plays music from your phone, and also has a built-in FM radio, which is great for gyms that broadcast the TV audio over treadmills via FM. A rocker switch adjusts the volume.
The SBH52 is optimized for managing phone calls. You can see who's calling and press a button to answer. You can also scroll around to see recent calls and call people back.
All this is taking place with a device the size of a pack of gum while your giant phablet is tucked away in a backpack or purse or is charging on the other side of the room.
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