Two of the largest phablets in the market are the Sony Xperia Z Ultra and Samsung Galaxy Mega 6.3. The Xperia Z Ultra was announced in June and launched in July while the Galaxy Mega 6.3 was announced in April and launched in June. The Xperia Z Ultra is Sony’s flagship with top of the shelf specifications while the Galaxy Mega is just a big phablet from Samsung. 
Lets check out how the Xperia Z Ultra and Galaxy Mega 6.3 compete against each other. httpv://www.youtube.com/watch?v=JhKr4ovh-f8 Design, Build Quality The Xperia Z Ultra looks huge and has a very good build quality with solid glass on the front and back. The Mega 6.3, other the other hand, is like all other Samsung Galaxy devices with an all plastic build and a plastic rim running across the device. The Xperia Z Ultra has a rectangular slab design with rounded corners and edges while the Galaxy Mega has smooth corners and curved edges. Along the device, Z Ultra has a brushed Aluminum finish while the Mega 6.3 has a plastic rim. The Xperia Z Ultra is dust and water resistant which expands its usability. 
In terms of dimensions, the Xperia Z Ultra is taller and wider than the Mega 6.3, but thinner. In terms of weight, the Xperia Z Ultra is heavier at 212g while the Galaxy Mega weighs around 199g. On the front of the phones, we have the display above which we have the earpiece and front cameras along with ambient and proximity sensors. We have the camera and sensors on the left side of the earpiece in the Xperia Z Ultra while they are on the right side on the Galaxy Mega. The earpiece is along the top edge on the Z Ultra. 
There are no navigation keys on the Xperia Z Ultra and hence all the navigation is restricted to on-screen buttons which eats away valuable screen space. The microphone is along the bottom edge on the Xperia Z Ultra. While on the Mega, below the display, we have the physical home button and there are capacitive touch keys on either side. 
On the right side of Z Ultra we have the volume rocker, the iconic Sony power lock button, covered microSIM, microSD card slots and the uncovered 3.5mm audio jack but on the Mega 6.3, we have just the power lock key. 
At the bottom, we have the loudspeaker on the Xperia Z Ultra while we have the microUSB port and microphone on the Mega 6.3. 
On the left side, we have a dock connector at the center and a covered microUSB port on the Xperia Z while on the Mega 6.3, we have the volume rocker. 
On the top of Xperia Z Ultra, we have just the secondary microphone while we find a 3.5mm audio jack, IR blaster and secondary microphone on the Mega 6.3. 
The back of both the phones is quite different as the Xperia Z Ultra has a plain reflective glass while the Galaxy Mega has a textured back that it borrows from the Galaxy S4. The back of both the devices are glossy and attract fingerprints. Both the devices have 8MP cameras and it is found on the top left side in the Z Ultra while we find it on the top center in the Mega. The camera on Mega 6.3 comes with an LED flash. 
The back cover of the Xperia Z Ultra is not removable while Mega 6.3 has removable back cover. Removing the back cover, we see the hot-swappable microSD card and the microSIM card slot. 
Overall, the Xperia Z is huge and feels huge. One handed usage is difficult especially with the rectangular slab design and flat edges. The Galaxy Mega is almost equally huge and has the same old Samsung’s all plastic build and design language, but because of its curved edges, it fits better in the hand. Display The Xperia Z Ultra has a 6.44inch Full HD Sony Triluminous display while the Galaxy Mega 6.3 has a 6.3inch HD SC-LCD display. The Xperia Z Ultra has a pixel density of 344ppi while the Galaxy Mega has a pixel density of just 233ppi. 
In terms of brightness, both the displays were quite good, but the Galaxy Mega was slightly ahead. In terms of color saturation, contrast, viewing angles the Xperia Z Ultra was ahead of the Galaxy Mega 6.3. Because of the high pixel density, images were more crisp on the Z Ultra. Overall, we liked the display on the Xperia Z Ultra. Hardware and Performance The Xperia Z Ultra is one of the first devices to be powered by the Snapdragon 800 SoC and is clocked at 2.2GHz, has 2GB RAM and graphics is taken care by Adreno 330 GPU while the Galaxy Mega 6.3 is powered by the 1.7 GHz Dual Core Snapdragon 400 SoC, has 1.5GB RAM and Adreno 305 GPU. 
The Xperia Z Ultra comes with 16GB of internal storage while there 8/16GB variants(we have the 16GB variant) in the Galaxy Mega. Both the phones have microSD card slot for storage expansion. Out of the 16GB, Z Ultra has around 11.7GB user accessible memory while we have a slightly higher 12.03GB space in Galaxy Mega. 
Out of the 2GB RAM, Z Ultra has 1.8GB usable RAM out of which 1.1GB is free when the device is idle. In the Galaxy Mega 6.3, we have 1340MB usable RAM out of the 1.5GB RAM and when the device is idle, around 720MB RAM is available. 
The better processor and quad-core along with extra RAM clearly gives the Xperia Z Ultra an huge advantage in terms of performance. The Xperia Z Ultra is faster in opening apps and switching between them. In benchmarks, the Xperia Z Ultra easily beat the Galaxy Mega. Camera Both the phablets have an 8MP camera at the back and the Xperia Z Ultra has a 2MP camera at the front while the Mega 6.3 has a 1.9MP snapper. The Xperia Z Ultra does not have a LED flash at the back which is a huge surprise given the price of the device and the flagship status while the Galaxy Mega has a single LED flash. Both the devices are capable of 1080p Full HD recording with stereo sound from the rear camera while only the Z Ultra records 1080p videos through the front camera. 
The camera UI is quite different on both the phones. Various shooting modes like HDR, Panorama and burst mode is available on both the devices. Xperia Z Ultra has a picture effect mode that has 9 effects with live previews. The Galaxy Mega has its camera app borrowed from the company’s flagship – Galaxy S4. In terms of image clarity, the images and videos of Galaxy Mega were much better with less noise, more details and better contrast and saturation. You can check out the camera comparison video right below. httpv://www.youtube.com/watch?v=-Jld7_BNVXQ Software features Both the devices run on Android 4.2.2 Jellybean and come with manufacturer’s skin for their UI. Xperia Z Ultra comes with Sony’s Timescape UI and has Sony’s small-apps feature which lets you choose a miniature version of the app that can be placed anywhere on the screen. Samsung’s Galaxy Mega has lots of software features like Smart-stay, smart rotation, S-Beam, Multi-window and Pop-out videos. There is no stylus on both the phones, however, Sony has claimed that anything like a stylus like pencil can be used to write on the screen. In terms of software, Galaxy Mega is ahead of the Z Ultra. Gaming Both the phones are quite good for gaming and the Xperia Z Ultra is excellent because of its excellent and bigger display. The Xperia Z Ultra is powered by a new generation processor and GPU which gives it a clear advantage in the gaming. All the games run very smoothly and have rich graphics on the Xperia Z Ultra giving it an advantage. Battery and Connectivity The Xperia Z Ultra has a 3050mAh battery while the Galaxy Mega 6.3 has a 3200mAh battery. In terms of battery life, the one on the Galaxy Mega is much better because it has to power a less powerful processor and lower resolution screen. In terms of connectivity, both the devices are equipped with features like WiFi(802.11 b/g/n/ac, Bluetooth, 3G, NFC, WiFi Direct, USB OTG and microUSB(MHL) connectivity. Conclusion The Xperia Z Ultra and Galaxy Mega are similar products for completely different buyers. The Z Ultra is flagship stuff and retails for Rs. 45,000 while the Galaxy Mega 6.3 is aimed at higher mid-range buyers looking for a huge device. 
Advantages of Xperia Z Ultra over Galaxy Mega
- Better and slightly bigger display
- Better performance
- Better for media consumption and gaming
- Better build quality
Advantages of Galaxy Mega over Xperia Z Ultra
- Relatively cheaper
- Better camera
- Better software features