With the pace of smartphone evolution moving so fast, there's always something waiting in the wings. No sooner have you spied the latest handset, then there's anticipation of something else, the next big thing to envy.
We've rounded up the best smartphones for 2015, those we consider to be the best across all platforms, and we've regularly updated that list as the smartphone world has evolved.
Here we're looking at those phones that haven't yet launched, those we know are coming, or are anticipated. We'll be updating this list on a regular basis, with those device rumours we think are credible and exciting, and devices just announced but yet to hit the shelves.
A new HTC hero phone
HTC is planning to release another hero handset in 2015. HTC chair and CEO Cher Wang has confirmed that there will be a new "hero product" launched in the smartphone category in October 2015.
Currently the flagship for most of the world is the HTC One M9, but there's also the HTC One M9+, HTC One ME and HTC J Butterfly 3, all of which mix the specs up a little more.
There's currently little to go on for this rumour, but previously, HTC has used October to launch the HTC Desire Eye (2014) and the HTC One max (2013), so another handset launch isn't entirely out of the question.
However, with the M9 not being received quite as well as the M8 that it replaces, HTC really needs to find a hero to shake things up and reassert itself. We suspect any new device will launch with Android 5.1 and Sense 7 and is likely to address the camera specifically, something that's attracted criticism in the current hero handset.
The Samsung Galaxy A8 recently cropped up in certification, so it looks like Samsung's A family is growing, quite literally.
The Samsung Galaxy A8 is said to sport a 5.7-inch display with a full HD resolution and powered by an octo-core Qualcomm Snapdragon 615 chipset. Those specs put this out as a more affordable mid-range phablet, rather than a challenger for the forthcoming Galaxy Note 5.
But the A8 is said to be super-skinny at 5.94mm thick, so it will have that accolade to its merit.
There's said to be a 5MP front camera and 16MP rear camera, as well as a 3,050mAh battery to keep things powered up. We're hoping it brings the fantastic experience of the Samsung Galaxy S6 to a larger but more affordable device.
There's no word on a release date, but as it's passed through certification, it probably won't be far off.
OnePlus is best known for a slightly viral approach to marketing its smartphone, using an invite-only system to make availability more exclusive. The OnePlus One was a huge hit with smartphone fans, and the OnePlus 2 is set to repeat the act.
OnePlus, fortunately, hasn't been shy of sharing some of the details about this forthcoming device. First, we know the OnePlus 2 will be made available through the same invite-only system as the OnePlus One. We know it will be appearing in Q2 or Q3 of 2015, so we're expecting a summer launch.
Additionally, OnePlus has confirmed that the OnePlus 2 will feature USB Type-C, adapted to offer enhanced features. The company says it will be the first handset available with USB C, again hinting at an imminent release date.
The next nugget of information that has been confirmed by OnePlus is that the OnePlus 2 will be powered by the Qualcomm Snapdragon 810 chipset, but that it's not going to struggle from overheating, as some others have.
Rumours are suggesting the new device will come with a 5.5 or 6-inch display, sporting a 1080p or QHD resolution. There have also been claims of a 16-megapixel rear camera, 5-megapixel front camera, 32GB storage and a 3300mAh battery.
Yes BlackBerry fans, it looks like the Passport could be getting a makeover, if the leaked specs for a handset codenamed Oslo are anything to go by.
BlackBerry loves the Passport, as do many die-hard BB fans, even if it's not quite so widely loved in the consumer segment. This revised version appears to change the materials for more of a retro look, with a silver metal and plastic frame and a rubberised back for grip.
It's said to have a Qualcomm Snapdragon 800 processor, 3GB of RAM, 13-megapixel camera and a massive 3,450mAh battery. There's no word on whether this is a new device, a carrier variation or something for a new market, although it's reported to be coming to Europe.
Samsung follows an annual release cycle and while the Galaxy S series takes the beginning of the year, the Galaxy Note series tends to be towards the end - traditionally at IFA in Berlin. If this cycle continues, it should mean we see the Galaxy Note 5 announced on or around 2 September 2015.
There has been talk of two devices, a traditional Note along with a dual-edge device, but of course, nothing has been officially confirmed yet. A 5.9-inch display with an Ultra HD Super AMOLED for the standard Note 5 has been touted and other rumours have claimed Samsung will follow the same design as the Galaxy S6, introducing a metal and glass finish.
Other rumours have suggested an 18-megapixel or 21-megaixel rear camera, coupled with a 5 or 6-megapixel front camera, up to 128GB of internal memory, a fingerprint scanner and a USB Type-C.
In terms of power, there have been claims of the Snapdragon 810 chip supported by 4GB of RAM, but it has also been speculated the processor will be taken in house, as Samsung recently did with its Galaxy S6 and Galaxy S6 edge devices.
Google is more than likely working on its next Nexus smartphone and while Motorola and LG have both had the pleasure of partnering with the software giant in the past, rumour has it Huawei could be making the next device.
Gizmo China claimed Huawei is on-board to produce the next Nexus phone, which will replace the Motorola-made Nexus 6. It has been suggested it could feature a 5.7-inch OLED display from Samsung, with a 1440 x 2560-pixel resolution.
Huawei tends to pack devices with its own Hi-Silicon Kirin chip, but the next Nexus device will probably come with Qualcomm's Snapdragon 810 chipset instead. Gizmo China didn't shed any other details about the phone, though the rumour mill is hoping it will ship soon with 4GB of RAM.
Now that we've had a few details about Android M, we fully expect the next Nexus to have hardware to support the new features in Android M - namely a fingerprint scanner and USB Type-C. We're expecting Android M and the new Nexus to launch in late 2015, October would fit with Google's annual cycle.
The first and second generation of Moto X were announced in August 2013 and September 2014, when Motorola was owned by Google. The company has since been taken over by Lenovo and a third generation of the device is rumoured to be in the works. The Lenovo chairman has confirmed that a new Moto smartphone will be launched in the summer and we're hoping it's the Moto X.
A website called STJS posted a leaked spec sheet for the third Moto X, claiming the phone will feature a 5.2-inch QHD AMOLED display, a Qualcomm Snapdragon 808 processor, 4GB of RAM, 32/64GB of memory, a 16-megapixel Clear Pixel camera, a 5-megapixel front-facing camera, and a 3280mAh battery.
A Verizon engineer named Jose Arturo also revealed on Google+ in April that Motorola plans to add a front-facing flash for selfies and microSD support to the upcoming phone, which was spotted by Droid-Life before the post was deleted.
Other rumours are currently thin on the ground, but if Lenovo sticks to the previous release cycle, we can expect to see plenty more speculation in the coming months. The Moto X has also dropped in price recently, suggesting Moto is trying to clear out old stock.
Just as the sun rises and sets, there will be a new iPhone in 2015. Following the patterns of update cycles of the past, it will be the iPhone 6S, and chances are, it will have the same design as the iPhone 6, making a few updates in a few places.
You can expect the same size display and resolution, but you might see the introduction of Force Touch on the display. This new method of interaction was introduced on the Apple Watch as well as the new MacBook, so it makes sense for it to come to the iPhone 6S and new iPads.
Apple previewed iOS 9 at WWDC in June, announcing that the new software would be available in "fall" 2015. It will make its debut on the next-gen iPhone, but from a software point of view there are few clues about what new hardware might be coming. We know that Apple Pay, Siri, Maps and other features will be updated.
There's also the rumour circulating that the iPhone 6S will use the new aluminium that Apple developed for the Apple Watch. This is said to be strong, but 60 per cent lighter than other aluminiums. With Bendgate blighting the iPhone 6 Plus launch, a stronger material might fix that problem.
The Moto G has been a storming success for Motorola, redefining expections for an affordable Android handset. It looks like the next-gen Moto G is in the works.
The Moto G second-gen was released in September 2014, so the appearance of a third-gen device fits in nicely. There's been a 4G update this year, but it looks like there's going to be a new device launch at or around IFA 2015.
It's suspected to have a 5-inch 720p display, run on a Qualcomm Snapdragon 410 chipset and pair a 13-megapixel rear camera with a 5-megapixel front camera. These details came from a substantial leak, although it's been said that's a prototype device, so take it with a pinch of salt.
The Sony Xperia Z4 was announced in Japan on 20 April 2015. Many expected a global launch for Sony's new handset, but Sony made it clear that the Xperia Z4 was for Japan only, with the newly announced Xperia Z3+ heading for the rest of the world instead.
Both the Xperia Z4 and Xperia Z3+ are incremental updates over the Sony Xperia Z3, sticking to much the same design, but boosting the specs in some areas - mainly the chipset and the front-facing camera. It's a blink and you'll miss it difference.
The Sony Xperia Z3+ has been announced featuring the same specs as the Xperia Z4, meaning the same OmniBalance design but with a capless Micro-USB charging port, a 5.2-inch Full HD display, 20.1-megapixel rear camera and 5-megapixel front camera. A Snapdragon 810 and 3GB of RAM will also be on board and it will be slightly slimmer and lighter than the Xperia Z3 at 6.9mm and 144g.
The Samsung Galaxy S6 active is official, but it is an AT&T exclusive, so currently it's a little limited in its availability.
However, this handset has a number of desirable features. It brings the specs you'll find on the regular SGS6, so you have the powerful octa-core Exynos chipset, and the Quad HD 5.1-inch display, as well as that excellent camera around the rear.
There are tweaks to make this phone rugged of course, with an IP68 rating. The capacitive recent apps and back buttons are replaced with physical buttons, designed to make it easier to use when wet.
And it comes in a choice of glorious blue or white camo and who doesn't want a rugged camo smartphone? No one, that's who.
The HTC J Butterfly 3 is another smartphone many won't be able to buy, sitting on KDDI's Au network in Japan and unlikely to appear elsewhere. That said, it could be possible that HTC will release a model with similar specs to this device, but call it something else for the rest of the world.
The HTC J Butterfly 3 has a 5.2-inch Super LCD3 with a 2650 x 1440 pixel resolution, Qualcomm Snapdragon 810 chipset with 3GB of RAM and 32GB of internal storage, with support for microSD expansion. It also features a 13-megapixel front camera, like the Desire Eye, and the Duo Camera on the rear with a 20-megapixel sensor, like the HTC One M9+.
All this hardware is held together with Android 5 Lollipop and Sense 7, so you get all the features you expect, packed into a waterproof plastic body. It's arguably more flagship than the HTC One M9 so here is hoping the Taiwanese company will launch a similar model this side of the water.
HTC One M9+
There were rumours of the HTC One M9+ before the M9 launched. This phone is now official, following a launch event in China. It's pitched at the Chinese market first and there's no word whether it will ever be seen outside Asia.
The HTC One M9+ has a 5.2-inch Quad HD display and is powered by an octa-core MediaTek chipset. There is a fingerprint scanner on the front, while a 20-megapixel Duo Camera sits on the rear.
In some ways it's again more progressive than the M9 flagship that was launched in March, with HTC looking to other hardware manufacturers, experimenting with that camera, but still offering high quality construction.
We're hoping it ventures outside of Asia, it certainly moves things on for HTC.
Not only did Huawei unveil a new flagship recently, but it is partnered by a huge compadre, the Huawei P8max.
This is a huge 6.8-inch device, so it's closer to a tablet than a smartphone, offering the same quality design and build as the smaller model, but also the same resolution at 1920 x 1080 pixels. That makes it pretty low in terms of pixel density.
You can expect plenty of power and there's a huge battery that should give you around two days of use. There's also a pair of clever cameras, offering promising performance, although Android is heavily modified again with Huawei's Emotion UI.
You should be able to get all this for less than many phablet rivals though, with a €549 price tag already announced.
The Huawei Mate 8 has leaked on a roadmap that suggested it will arrive as soon as next month, with June as the listed date. The leaked roadmap appeared on Mobile-dad and the leaked specs suggest it could be an exciting phablet when it does appear.
According to the rumours, the Mate 8 should feature the same size screen as its predecessor at 6-inches, but it will get a pixel bump from Full HD to Quad HD. It is also expected to come with a Kirin processor and the camera is listed at 16-megapixels.
The only problem with the Ascend Mate 8 is an international release. The Huawei Ascend Mate 7 was supposed to get released worldwide but it didn't get far out of China, despite being a huge success there, so we aren't getting our hopes too high for the Mate 8 just yet.
Microsoft's executive vice president Stephen Elop announced a new Lumia would be arriving this year and since then, renders have been doing the rounds. The latest renders are of the rumoured Lumia 940, also known as Talkman, and the Lumia 940 XL, also known as Cityman.
The handsets have not been officially announced yet, but rumours suggest the Lumia 940 will come with a 5.2-inch Super AMOLED screen with a 1920 x 1080 resolution, while the Microsoft Lumia 940 XL is expected to feature a larger 5.7-inch screen with higher 2560 x 1440 resolution.
There should be a 32GB model of the Lumia 940 with 64-bit hexa-core Snapdragon 808 processor or 64GB and 128GB versions with 64-bit octa-core Snapdragon 815 processors and both will have 3GB of RAM and Intel RealSense. The rear camera is tipped be a 25-megapixel PureView with Zeiss lens, triple-tone LED, 4K video and OIS while the front-facing camera should be 5-megapixels, while the battery is expected to be 3250mAh.
The Lumia 940 XL is expected to have the same specs as the 940 but with 4GB of RAM and a larger 3950mAh battery, along with digital pen support. Both handsets are expected to launch as the flagship phones when Windows 10 is released.
Sony Xperia Z4 Compact and Ultra
The Sony Xperia Z4 Compact is apparently going to arrive with 3GB of RAM, a 20.7-megapixel camera, 32GB storage, and a 4.7-inch screen with 1080p resolution. You can also expect a 3000mAh battery, Cat 9 LTE, wireless charging and IP68 water and dust proofing.
The Sony Xperia Z4 Ultra should arrive with a 6.44-inch display with a QHD resolution. It should also come with 3GB of RAM but a smaller 16-megapixel camera and larger 4000mAh battery. Unlike previous versions of the Ultra this model should also come with a stylus.
Sony has made a start on the Z4 family with a new 10-inch tablet, followed by the Japan-only Xperia Z4 but as the Z4 name doesn't seem to be making it's way to the rest of the world, we are taking the compact and ultra rumours with a pinch of salt for now.
Asus was one of the first companies to launch a new device in 2015 with the Asus ZenFone 2 launching at CES 2015 in Vegas.
The company stuck with Intel for the hardware, with an Intel Atom Z3580 paired with 4GB of RAM, which should make for a really powerful handset.
There's a 5.5-inch display, with 1920 x 1080 pixel resolution as well as a 13-megapixel camera on the rear. Asus is making great claims about this camera, saying it will offer low light performance like you haven't seen before but we'll be the judge of that when we get it in for review.
The ZenFone 2 has rear volume controls, like the LG G4, and it ships with Android 5.0 Lollipop skinned with Asus' Zen UI.
Fortunately, despite some premium specs, the ZenFone 2 comes with the $199 starting price tag. We're yet to hear exactly where it will be on sale, however.
We didn't see this one coming, until Asus teased "optical zoom" in an oh-so-obvious way. But Asus now has a smartphone with optical zoom that was announced at CES 2015.
There aren't many cameras with optical zoom around and the ZenFone Zoom is a world away from the Samsung Galaxy K Zoom. Samsung's model is more like a camera, however, with 10x optical zoom and a 20-megapixel sensor, along with Xenon flash. The Asus, however, is fairly slimline, cramming the 3x optical zoom 13-megapixel camera into a body that's still pretty slim.
To assist that camera is laser autofocusing, but we're yet to see if this all fuses together nicely, or if it's a mish-mash experience.
Elsewhere, the Asus ZenFone Zoom has a 5.5-inch display and will launch with Android 5.0 Lollipop, along with Zen UI. It's still some way off, however, with no word on when it might be available.
This rumour is a little on the loose side, but a leaked image appeared showing a Lumia model with a big camera bump on the rear. The Lumia 1020 was a mobile photography star, but has never been replaced and all of Microsoft's recent devices have been at the budget end of the spectrum.
There's a chance that you're looking at a new high-end PureView model, known as the RM-1052, but equally it could be a prototype of the cancelled Nokia McLaren.
It's nice to dream that Microsoft Devices will fill the high-end with a 5-inch Windows 10 device with a great PureView camera and while we're not convinced by the bodywork, the metal and plastic fusion doesn't look like a finished consumer device, it could be the birth of a new photography star for 2015.
As mentioned previously, Stephen Elop announced at MWC that a new flagship would be coming later in the year, so Windows 10 will have itself a new device to play on whether that is this one or the 940 family is not clear.
Created by Motorola, and now shifted over to Google after the sale of Motorola to Lenovo, Project Ara isn't due until late 2015 but is essentially an exoskeleton that allows users to modify what parts they want. That way someone that wants to spend the bulk of their budget on the camera, but doesn't need as much storage, can chose to upgrade that way. Perhaps one person will skip NFC in favour of faster 802.11ac Wi-Fi, for example.
There should also be third party components on offer that will allow for competitive pricing as well as new types of parts - like sensors. A person with diabetes may want a blood sugar sensor where another may not.
Users can also looks forward to different textured options that they can 3D print off at home themselves. The speed this phone can develop at, without costing us as much, is very exciting indeed.