(Pocket-lint) - HTC Sense 6.0 has launched on the HTC One (M8), the new flagship HTC device for 2014. It's also being referred to as Sixth Sense, although it appears listed in the device as Sense 6.0.

We've had the new HTC One for some time, giving us the chance to dive into HTC Sense 6.0 and see what has changed from HTC Sense 5.5, the most recent version on the original HTC One. In mid-May 2014, the original HTC One (M7) Sense 6.0 update began, hitting the UK in June.

The HTC One (M7) launched with Sense 5.0, which was quite the departure for HTC, introducing BlinkFeed and changing much of the user interface. It made things simpler, but retained that distinctive HTC identity.

HTC Sense 5.5 was introduced on the HTC One max later in 2013 and evolved Sense 5 a little further, mainly adding a range of additions to BlinkFeed and tinkering with the Gallery.

In this review we're comparing HTC Sense 6.0 on Android 4.4 KitKat on the HTC One (M8) with HTC Sense 5.5 on Android 4.4 KitKat on the HTC One (M7). Grab your slippers, we're going deep.

Before we dive into the granular details, one of the big differences between M7 and M8 is that the new device has on-screen controls. This means that you have back, home and recent app buttons on the bottom of the display, rather than in the bezel area below, something you'll notice in the screenshots throughout this review.

We'll not delve too deep into the changes that makes to the device - you can read all about that in our HTC One (M8) review - and when HTC Sense 6.0 comes to the older HTC One, it will still have capacitive buttons.

The arrangement of the launcher in Sense 6.0 is very much the same as it was before, with HTC retaining the same icons for things like the phone and messages. The shortcuts now sit on a clear background rather than in the solid bottom bar of Sense 5.5.

That gives Sense 6.0 more of a KitKat feel than Sense 5.5, but we suspect that some of that is by necessity because of the on-screen buttons - having a solid bar incorporating both navigation controls and shortcuts would have looked ridiculous.

That translucency runs deeper than it did in Sense 5.5, as now the lock screen notifications are translucent, ditching the shaded bar for white text instead. We like it, it reflects KitKat much better in Sense 6.0 than previously.

There's another advantage though, as when you are viewing BlinkFeed, it scrolls behind the icons with a new smooth action, rather than articulating tiles from behind the shortcuts bar as it did on Sense 5.5.

It's a slicker and cleaner look.

As before, you have the option of setting BlinkFeed or a regular page as the default home, accessed when you hit the home button. We'll talk about BlinkFeed in more detail later. HTC refers to "normal" pages as the "widget panel".

The apps tray loses the top clock and weather widget in Sense 6.0, giving you more space for apps. It's a smart move, because even though we like HTC's weather clocks, when it eats a row of apps, it really doesn't help.

Again you can select the grid size (3 x 4 or 4 x 5) for the apps tray, you have search options, you can make folders and sort via most recent, alphabetical or custom, which is our preferred option.

Using folders means less scrolling up and down through the list when you have lots of apps, so is worth doing.

There's been a change to how you move and manage apps in the apps tray. In Sense 6, if you press and hold and app, you're taken straight to the home page to drop a shortcut, as you would be in Android KitKat's Google Now launcher.

If you want to put your apps into folder, you'll have to select the "rearrange apps" option in the menu, at which point you can create folders and move things around.

The icons running through the menus have been simplified greatly in Sense 6.0, making everything cleaner and more minimalist. Rather than the coloured iconography of Sense 5.5, things are now flatter and in single colours.

Icons in the menus are predominantly grey, picking up a colour highlight that's determined by the selected theme (more on that later). The Wi-Fi logo, for example, was previously a blue-bordered roundel with the logo in the centre. Now it's simply that central logo. The mobile data icon is now just a pair of arrows, rather than the bordered blue crisscross thing.

The fonts have slimmed down slightly too. There's less aggressive use of bold through the menus, and you can change the font device-wide if you wish, with Helvetica and LCD as alternative text styles.

Helvetica looks fine, LCD is a dramatic change, a little more difficult to read because of its complexity and density on the page.

Although colours have been stripped from menus, Sense 6.0 changes its relationship with colour slightly. Those who remember older versions of Sense will recall the mass of themes that were available in the Personalise menu.

There's something of a return to that with new theme options, but it's much more sophisticated than Sense of old. There are four on offer and each theme, except for a minimalist black option, has four linked colours associated with it.

These colours flow though different sections of Sense to create colour unity across various areas. The default theme gives BlinkFeed a green background and green highlights in switches and menu items, while communication apps, like email, messages and dialer, get a blue theme.

It's a nice effect, bringing a little more interest to some of the core apps, where previously you'd have either black, white, or grey.

The Personalise menu now includes more options, but for some reason the fonts are in the display settings menu, and we think they'd be more at home alongside the themes and wallpaper options here.

New to Sense 6.0 is a range of actions that HTC is calling Motion Launch gestures. HTC has had a number of motion controls for a while, like lowering the volume of the ringer as you lift the phone up, or silencing it when you turn it over.

Now there's a collection of new actions and critically, they all take place without you having to press the standby button to wake the device up. Some of this is thanks to new hardware in the sensor hub, allowing the new HTC One to remain aware without draining the battery. Because these actions are hardware dependent, they aren't present on the M7, or devices like the HTC One mini 2.

The Motion Launch gestures include a number of swipes from the sleeping screen. You can swipe left to open in BlinkFeed or right to access the widget panel/normal home pages. You can swipe up to unlock, or swipe down to access voice dialling.

All are useful, if you don't have security engaged, but if you have a pattern lock in place, you'll have to then enter that before you arrive at your desired location. The quick call voice dialling option can be set to bypass security, as does the quick launch camera option.

The quick call voice dialling option we're not so keen on, because we've triggered voice dialling accidentally on a number of occasions. We put the phone down on the table and swiped the screen in the process. It then listened to the TV and tried to call someone, so we've left it turned off.

Holding the phone in landscape and pressing the volume button will let you launch the camera directly, which is a useful addition.

Our favourite, however, is the double tap to wake. It's a handly option because you can double tap and glance at your lock screen notifications, and then double tap to send it back to sleep again.

HTC Sense has had a power saver feature for a number of years. This offers to dim the display, throttle the CPU and such like, to make your battery last longer.

New in Sense 6.0 is an extreme power saver mode. This will cut all unnecessary elements of your smartphone, with HTC claiming that extreme power saver will give you 30 hours of standby from 10 per cent battery on the 2600mAh M8 battery.

You can opt when it engages - at 5, 10 or 20 per cent remaining battery, or you can turn it on manually.

The interesting thing about extreme power saver mode is that it gives you a different interface. Background data is switched off, launch gestures are disabled, the display is dimmed, vibrations go as does Bluetooth, and you're left with an interface offering access to the phone, messages, email, calendar and calculator.

Essentially it becomes a dumbphone. It's a nice idea and when you're staggering home from the pub after a long day, it will get you back home, able to send messages or call a cab, but not harass people on Facebook or post drunken messages to Twitter.

We like the idea, but using the stock email client rather than giving you the option to pick your preference is slightly limiting.

One of the changes that comes with Sense 6.0 is how some of the apps are handled. Gallery, BlinkFeed, Zoe and the TV app are now independent, so HTC can update features on these things more frequently, without that being part of a wider Sense update.

That should mean that minor changes should happen more readily and faster than before.

Whether that means that older devices like the M7 will have to have a Sense 6.0 update before they get to take advantage of these updates, we can't be sure.

BlinkFeed is still very much a headline feature of Sense and in Sense 6.0, it's so much more refined than previously.

We mentioned when talking about themes that it will adopt a colour and that makes BlinkFeed a more pleasant place to browse. Scrolling behind the icons also looks better, but the change in animation makes the biggest difference.

BlinkFeed in Sense 6.0 has a better free scrolling action with bigger images and, like the apps tray, loses the top weather clock if you don't have it set as the default home location.

There are also more options for controlling your content. One of the new features is the integration of Fitbit results - with the Fitbit app preinstalled on some HTC One (M8) handsets - as well as recommending places to eat around mealtimes using Foursquare.

The latter option is very much about having a sixth sense, although we found it suggested KFC. Whether it will lead to a voyage of culinary discovery or a straight junk food binge, we're yet to determine.

When it comes to adding content there are now category icons rather than endless lists, although searching works just as well.

BlinkFeed looks better than before and the easy access through the launch gesture makes it quick to get to as well.

The camera is a strong focus of the new HTC One (M8), but without the duo camera setup, some of the new camera software elements won't be supported on devices that get updated to Sense 6.0. That's true of the HTC One M7, with none of the fancy features offered, but the same overall camera app design.

The camera now offers one capture button by default and that's for the regular camera. In the last few iterations of Sense, HTC has been pushing the instant photo or video option. Now, if you're after video, you'll have to head into the photo modes and select it.

That also brings with it a degree of consistency that was missing before. Previously you had photo and video buttons, then the Zoe toggle to the left and everything else was hiding in a menu.

With a new camera mode button you can access camera, video, Zoe, selfie, dual capture and panorama 360, which is very much like Android's native PhotoSphere option. Duo capture and Pan 360 aren't available on the HTC One M7.

However, there are still some options hiding in the menu. If you want to access the scene modes, they are in a menu. We don't mind that so much, but we wish that HDR was bundled into the major camera modes to make it faster to access, as that's a function we use regularly.

There are a lot of different scene options, as well as a new manual mode. This will let you set things like your max ISO or the shutter speed to get the effect you want. You can also save manual settings, so if you have a preference, you can set it up and save it.

There's the option to set the "makeup" level, so you can smooth your skin in a selfie. It might look a little too artificial for chaps, but those wearing real makeup might find it works nicely.

There will be plenty of information on the performance of the HTC One M8 camera in our review.

One of the big changes in Sense 6.0 is the addition of new photo effects. In Sense 5.5, "effects" was a selection of filters. These now appear in Sense 6.0 under filters, with effects being a whole different collection of tools.

Incorporated into these effects are all the old "retouch" options, now called "touch up", which mostly handle face editing.

The exciting stuff, however, comes from the ufocus, foregrounder, copy and paste, and dimension plus options. These aren't unique to HTC, as Nokia has done similar things in the past, but it's great to be able to apply these effects to a photo you've taken (in the case of ufocus) rather than having to use a specific shooting mode.

These effects use the second sensor on the HTC One (M8) to gather data, so they are not available on the single sensor devices, like the original HTC One.

The 3D effect is very clever. This uses that second lens data to give you a little 3D pop, so as you move your device around, the image moves with it. For example, for the ducks above, you move your device and you get a greater perception of 3D depth from the image. It's fun and unique.

Zoe has had a slight repositioning, both in terms of its capture functions and what you do with your Zoes once you've got them.

When it comes to capture, Zoe now offers more options. It still gives you moving capture, but it's not set in length. A quick tap will capture a still image, a longer press will give you that shot clip, but if you press and hold, it'll flip over to video capture.

This makes sense because Zoes are great for capturing something that's moving and turning it into straight video capture means that you don't miss the moment because the time limit for Zoe is reached.

There's a new Zoe app too and it's this that HTC wants to use to expand Zoes beyond an HTC exclusive existence. It replaces the HTC Share option of Sense 5.5, opening up the app when you choose to broadcast a video highlight.

The idea is to turn Zoes into more of a social network, letting you share and collaborate on those funky highlight videos with friends.

That means you'll be able to go to a wedding, for example, capture some great photos and video and then share a highlight video with friends using the Zoe app. Friends can add their own photos, remix the highlight video and so on, to build to a better final result. It's all about sharing and interaction.

At the time of writing prior to launch the app isn't available, but we'll update once we've had a chance to play with it in the real world.

With Zoe getting its own app, there's been a change in the Gallery, with the HTC Shares element now gone. We like HTC's Gallery because it's full of motion and in Sense 6.0, that's been expanded.

The Gallery now has fewer sections, offering Timeline, Albums and Location as top tabs. As before you get big images, with Timeline grouping video and photos together with the option of events, day, month or year organisation.

The Timeline effectively bubbles the video highlights section of Sense 5.5 up to the top level. Previously you'd have to enter an event or album and then swipe across, here it's an option as soon as you enter the gallery.

Those video highlights are available at the top of every section you enter thoughout the gallery. Where previously you could click on an album, then swipe, now you have that neat custom animation at the top as soon as you click through. It has a much higher prominence than previously.

You still get all the editing options for those videos, with new themes and the option to pick your content and music, much as you did before. When you come to share that highlight video, rather than HTC Share taking it, the Zoe app will open, as mentioned above.

As previously, you can access media servers direct from the Gallery, great for browsing content on your network, but there's also a new search option. This will let you identify an image and search for similar images, then save them to a new album.

The TV app has had a facelift, moving from a dropdown menu to sidebar menu, more in keeping with BlinkFeed and the wider Android world.

It serves a number of functions as it did before, letting you browse TV content, as well as being the home for the IR remote control. You can set your TV provider, programme in your devices and use your phone to control your home viewing.

There's a nod to online video services with Crackle integration, but with Watch, HTC's video service, shutting down, that's no longer an option in Sense 6.0.

But there's now a expanded social element to the TV app. In each programme or movie, you can flip over to a "fan talk" section. This will let you keep track of discussion on Twitter and you can add hashtags you want to follow.

There's also a new Live Sport section. This will feed you information of sports taking place, with score cards and again the option to flip over and add to the commentary on Twitter. There's the option to post right from the app, so if you see a score line you want to celebrate, it's only a click away.

The music app in Sixth Sense is the same as it was previously in Sense 5.5, letting you view by artist, album, songs and playlists. There's still the integration of media servers, as well as the option to search and the ability to update album art.

The only change is that the music app now picks up the colour themes so it's brighter than before.

BoomSound in Sense 6.0 on the HTC One (M8) takes the place of Beats Audio. There's the option to turn off BoomSound in the settings menu, but you can only do so when you have headphones connected - it can't be disabled when using the built-in speakers, which you could previously with Beats.

For older devices that launched with Beats, that option stays in place, effectively offering the same as BoomSound. You still get the Beats logo in the notifications bar as you did before.

We've covered the main elements of Sense but with some of the biggest apps breaking out - Gallery, Zoe, BlinkFeed, TV - Sense might never be quite as easy to analyse in one lump.

There are plenty of places where there are small changes - the move from dropdown menus to sidebar menus is a common shift, as is the adoption of theme colours in the apps, giving some parts of Sense a new look, even if the functionality remains the same as it did before.

There isn't a huge amount that appears to be hardware dependent, although we can't be sure if the launch gestures will come to older devices in an update or not. Obviously, some of the advanced camera options will be using that additional sensor, so we doubt you'll get the same editing features on other devices.

HTC Sense 6.0 is an incremental refinement of Sense 5. If you've used any of the 2013 HTC One, One mini or One max, then you'll be right at home. Most things are in the same places.

On the HTC One (M8), Sense 6.0 is incredibly slick and fast. We had no problems with Sense 5.5 on the M7, but side-by-side, the M8 is a far better experince. You can read all about that in our details HTC One (M8) review.

If you have any questions or observations, then please comment. HTC has said that Sense 6.0 will be coming to older devices, but hasn't confirmed a timeline.

READ: HTC One (M8) review

Writing by Chris Hall.