MWC 2015: The 6 most noteworthy smartphones

Mobile World Congress 2015, which opened in Barcelona this Monday, March 2 in the presence of King Felipe VI, has already seen the presentation of several new smartphones, including the highly anticipated Samsung Galaxy S6 and HTC One M9.

Samsung Galaxy S6 and S6 Edge

Due to launch in 20 countries on April 10, the South Korean giant's latest flagship phone will be available in two versions: the Galaxy S6 and the Galaxy S6 Edge. The latter model is the world's first smartphone with curved screens across both the right and left edges. Samsung claims the S6 will be sturdier than its predecessors thanks to its special metal case, but the battery is no longer removable and there is no microSD memory card slot. Pricing details have yet to be officially announced.

HTC One M9

As usual, HTC has placed the emphasis on styling with its new One, which has an aluminum monobloc design with accents in steel grey, silver or gold. 4G+ ready (up to 450Mbps according to the manufacturer), the One M9 runs the latest version of Android under HTC's customizable Sense 7 skin, which uses location data to adapt to the needs of the user with contextual widgets. The HTC One M9 will be available from April 2015.

ZTE Grand S3

The Chinese manufacturer ZTE came to Barcelona with the first smartphone equipped with the EyePrint ID technology, which allows the user to lock or unlock the device simply by looking into its scanner. Already available in China, the 5.5-inch Android KitKat (4.4) smartphone is due to launch in Europe and the US at the end of 2015.

Huawei MediaPad X2

Though it chose to turn the spotlight primarily on its new smartwatch, Huawei also presented a remarkable new smartphone in Barcelona. The MediaPad X2 is a phablet with a 7-inch screen (1200x1920px) and a thickness of just 7mm. Also 4G+ compatible, the new device runs Android with Huawei's EMUI layer. Pricing and availability details are unannounced.

Sony Xperia M4 Aqua

The Japanese manufacturer took advantage of MWC to reveal its new mid-range smartphone, which it claims is waterproof and has a battery life of up to two days. The Xperia M4 Aqua comes with Android Lollipop and is the brand's first device equipped with the octacore Qualcomm Snapdragon 615 processor. Its 'smart' 13MP camera is said to be capable of detecting up to 52 different types of scenes. The smartphone will go on sale in Europe this June.

Microsoft Lumia 640

Rather than unveiling a new premium smartphone in Barcelona, the American company chose to introduce a more affordable device compatible with its forthcoming multi-platform operating system. Available in two versions -- the 5-inch Lumia 640 and the 5.7-inch Lumia 640 XL -- the new smartphone packs a Qualcomm Snapdragon 400 processor clocked at 1.2GHz and 8GB of (expandable) storage. To be delivered with Windows Phone 8.1, the new Lumia terminals will be updated to Windows 10 after its release. Due to ship this spring in both a 4G version and a more affordable 3G version, the Lumia 640 and 640 XL will be available starting at €139 (around $155) and €189 (around $212) respectively, plus tax.