What is different?
Joining the Samsung Galaxy S5 and the Sony Xperia Z2, the HTC One M8 is the next big Android phone arrival in 2014. Last year's HTC One is still arguably one of the best Android phones out there, so the M8 has a lot to live up to.
We’ve already taken a look at how it compares to Samsung and Sony’s flagship phones, so how does it compare to its predecessor? We compare design and specs to find out if there’s really enough reason to make the upgrade from the old HTC One.
HTC One M8 video preview
We've had a go with the HTC One M8 ourselves. Want to see what it looks like in person? Watch our preview video below.
Difference #1: New Design
HTC is sticking with an aluminium unibody that uses more metal than its predecessor. As a result it's heavier at 160g - up from 143g.
It comes in Amber Gold, Metal Grey, Arctic Silver colours, and the One M8 is curvier around the edges than the One and has moved the headphone port from the top to the bottom of the phone. There's now a nano SIM tray on the left edge, and perhaps the most notable new addition is a microSD card tray that supports cards up to 128GB.
Difference #2: Bigger screen
iPhone 5S aside, smartphone screens are getting bigger. The Galaxy S5 now has a 5.1-inch display while the Xperia Z2 packs a larger 5.2-inch screen. The HTC One M8 swaps a 4.7-inch for a larger 5-inch Super LCD display.
It’s still Full HD 1080p resolution, though HTC claims there are improvements in black level response and contrast for a more vibrant display. Interestingly, the PPI pixel density count is down from 468 ppi to 441ppi - the size has increased, but not the resolution. That's still higher than the iPhone 5S and the S5, and should still mean decent levels of clarity for reading books or web pages.
Difference #3: More power
Joining the Xperia Z2, the One M8 runs Qualcomm’s new Snapdragon 801 quad-core processor clocked at 2.3GHz. That’s a significant upgrade from the quad-core Snapdragon 600 in the original One. The new CPU uses Krait 400 cores and an Adreno 330 GPU. That should give it plenty of gaming grunt as well.
HTC has also introduced a dedicated Motion Launch processor that works like to the M7 co-processor found inside the iPhone 5S. It handles the motion sensors to work more effectively with fitness-tracking apps - without sapping much battery at all in-use.
Difference #4: New camera
HTC has not budged from the 4-megapixel UltraPixel main sensor. It opts for larger camera sensor pixels, instead of more like the Nokia Lumia 1020. That means it can take in more light and offer better low light performance.
It also continues to use the same f/2.0 lens, but adds a second sensor that will help to ‘capture spatial awareness’. Other new features include a dual LED flash with two-tone LEDs. This is something included in the iPhone 5S camera and aims to bring more natural-looking results. Up front, HTC has moved to a 5-megapixel with a f/2.0 lens so expect your selfies and video chats to look a lot more impressive.
Difference #5: KitKat 4.4 and Sense 6
The original One previously ran Android 4.3 with HTC's Sense 5 UI overlaid on top. After numerous delays, the Android 4.4 KitKat update is now available for the older phone, and the M8 will have KitKat out of the box.
It will also be the first HTC phone to get the new Sense 6 UI to keep things running slick. HTC has made some tweaks to the look and feel of the Sense UI. And for those who like the BlinkFeed social media feed, it's still there as well.
Difference #6: Bigger battery
In our time with the HTC One, the 2,300mAh battery struggled to make it through a day. The only way to get it through two full days was to restrict the wireless connectivity. Thankfully the M8 now has an improved 2,600mAh battery to improve matters and HTC is claiming its new Quick Charge feature will charge up the phone to 80 per cent of its capacity in one hour. Sounds promising.
What's the same?
We've already mentioned the screen resolution will be on par with the original HTC One and there'll be plenty of the same connectivity options as well including MHL to connect to a HD TV, USB OTG and NFC for wirelessly connecting to a compatible speaker or headphones.
The BoomSound speakers that make a good impression on the original are still in place with new loudness-increasing digital signalling processing (DSP) and re-designed piezo drivers.
More: HTC One M8 vs Samsung Galaxy S5