There are some who find carrying a single device well worth the phablet’s price of admission : bulky display sizes larger than 5 inches and smaller than 7 inches. After all, Samsung’s Galaxy Note series has been quite successful. The Korean electronics giant sold over 10 million units of the original model, with the sequel — released last fall — on track to do even better.
But for the majority of users, phablets are in-between devices that don’t necessarily fit in with mobile lifestyles. The devices are either too big to carry around as a phone or too small to work as a tablet.
While the Galaxy Note has been a success, the sales of the device pale in comparison to more traditional mobile devices. Especially when you consider the fact that Samsung shipped 70.7 million smartphones  in the first quarter of 2013 alone, according to IDC.
Sony’s upcoming Xperia Z Ultra , however, could leverage accessories and wearable technology to walk among the phab giants.
The Xperia Z Ultra is an ultrathin (6.5-milimeters) phablet with a very big (for a phone) 6.4-inch screen. It’s even larger than Samsung’s mammoth 6.3-inch Galaxy Mega. The phablet gets its power from a Qualcomm Snapdragon 800 2.2GHz quad-core processor and runs Android 4.2 Jelly Bean. As if those specs weren’t impressive enough, it’s even supposed to be waterproof (not just resistant) in depths up to five feet.
The real secret sauce lies in the device’s interoperability with smart peripherals that promise to move the phablet category forward with buyers.
In an article on Computerworld , Mike Elgan sketches out how the success of phablets requires more than the right balance between display size and smartphone/tablet functionally:
To me, a true phablet eliminates the need and even the desire to carry or own two devices smaller than a laptop, even for people who are able to easily afford two devices.
Instead of thinking about phablet computing as a device category, think of it as a new behavior, paradigm or lifestyle in which a small-tablet-size device forms the centerpiece of mobility in an elegant, socially acceptable and convenient way.
This just isn't happening yet. But why?
It turns out that the secret is not just figuring out the perfect intermediate screen size. The way to achieve the phablet lifestyle is to combine the right phablet with wirelessly connected wearable computing.
When paired with Sony’s recently announced Smart Bluetooth Handset SBH52 , you won’t have to remove the bulky (albeit skinny) Xperia Z Ultra from your briefcase or purse to answer a call. Simply push a button and talk into the Smart Bluetooth Handset SBH52 directly or through included earbuds, and view caller ID information and text messages on the device’s low-resolution display. It pairs with the Xperia Z Ultra via NFC and, at about the size of a pack of gum, the Smart Bluetooth Handset SBH52 clips unobtrusively to clothing.
Sony also introduced its latest SmartWatch accessory, the SmartWatch 2 . This Android-run peripheral pairs (also via NFC) with Android smartphones to let users handle calls from their wrist, which is especially useful when your smartphone happens to be a large phablet, such as the Xperia Z Ultra. As with the Bluetooth Handset SBH52, you can wirelessly check messages and control music from the SmartWatch 2.
Sony intends to ship the SmartWatch 2 and Smart Bluetooh Handset SBH52 in September and the Xperia Z Ultra sometime during the third quarter. No word on pricing for any of the devices.
These new Sony accessories highlight how phablets require “wearable devices to make them powerful, viable and mainstream, as well as acceptable in business,” writes Elgan.
If the Smart Bluetooth Handset SBH52 and SmartWatch 2 perform as advertised — by integrating seamlessly and extending the calling capabilities of the Xperia Z Ultra — then users can focus less on the complexities of the device’s in-between status and more on the versatile functionality provided by a smartphone big enough to let you comfortably use a digital menu.