(Pocket-lint) - Motorola has announced three new devices at a launch event in London, including two new additions to the Moto X flagship range. The Moto X line was originally introduced in 2013 and it has seen annual updates since, making this the third generation of the popular smartphone.

The Moto X has also been one of the most customisable phones to date thanks to Moto Maker and we had a lot of love for the 2014 model. It was an uncluttered Android marvel that we felt was great value for money so, naturally, we have high expectations for the 2015 models.

So what's new with the two additions to the line-up and how do they compare to the 2014 model? Join us for some number crunching and spec slashing to see how these models compare.

Different screens, different sizes

The 2014 Moto X has a 5.2-inch display, while the Moto X Play ups that to 5.5-inches, and the Moto X Style goes all out with a 5.7-inch display.

However, it's not all about screen size. The Moto X Play utilises the same 1920 x 1080 pixel resolution as the 2014 model, but as it's spread out over a slightly larger 5.5-inch area it has a slightly lower pixel density (400ppi, not 423ppi as per the 2014 model). The real winner in among the trio is the Moto X Style, though, with its Quad HD (1440 x 2560 pixel) resolution making it the most pixel-dense of the bunch at 515ppi.

All three models feature AMOLED panel technology, which carries the traits of that technology: deep blacks and added vibrancy to the colours. There's real punch to reds, a vibrancy that's not wholly realistic, but if you like such punch then you're in luck whichever model you choose.

Curved backs, thicker 2015 designs

Interestingly the three models aren't as drastically different in size as their respective screen sizes make them sound. Starting with the 140.8 x 72.4 front-on dimension of the Moto X 2014, the Moto X Play is the next largest, at 148 x 75mm, while the Style is the largest, at 153.9 x 76.2mm. Despite that the largest model is still smaller than an iPhone 6 Plus, despite its technically larger 5.7-inch screen size.

Thickness is variable in the 2015 Moto X models, thanks to a curved design for comfort in the hand. The Moto X (2014) is a fairly chunky phone at 9.9mm thick, but both the Style and Play are thicker still. The Style's curve varies from 6.1-11.06mm, while the Play is slightly more trim at 8.9-10.9mm.

The 2015 models have much better cameras

Motorola isn't mucking about with the Moto X Play and Moto X Style. Both the new flagships feature a 21-megapixel rear sensor, paired with an f/2.0 lens. That's a significant resolution jump compared to the 13-megapixel f/2.2 rear snapper of the Moto X (2014).

Both 2015 models also feature dual flash, plus a 5-megapixel front-facing camera. The Moto X Style adds a front-facing flash, something that both the Play and 2014 Moto X lack.

The camera was one of the few features we weren't overly impressed with when it came to the Moto X (2014) so with a bit of luck the extra megapixels both front and back will improve our opinion for the Moto X Style and Moto X Play.

You'll find the same features on the new model that were included on the Moto X (2014), such as tap anywhere to capture, 4K UHD video capture, slo-mo video capture and burst mode so the user experience should be similar.

The Style goes super-powered, the Play goes mid-power

In an interesting move, the Moto X 2014 is sandwiched by the two 2015 models in terms of power. The Moto X Style brings a hexa-core 1.8GHz Snapdragon 808 processor with 3GB RAM, putting it ahead of the 2.5GHz Snapdragon 801 and 2GB RAM of the Moto X 2014. The new Moto X Style, on the other hand, opts for a 1.7GHz octa-core Snapdragon 615 processor with 2GB RAM.

There are expected to be 32GB or 64GB storage option choices available, as no Moto X smartphone offers microSD support. It would have been nice to see microSD support added as this was one of our qualms with the 2014 model, but with the Style's fixed back it's perhaps no surprise.

The Moto X Play has the largest battery capacity

In terms of battery capacity, it's the most affordable option that has the most capacious battery. The Moto X Play delivers a 3630mAh capacity, while the Moto X Style matches LG G4 territory with a 3,000mAh offering. Compared to the 2014 Moto X, with its 2300mAh battery, both the 2015 models offer a big step forwards. However, with the Style's Quad HD screen, it runs the risk of the battery life depleting faster than it ought to - much like the LG G4.

The other big news on the battery front is turbocharging, making for super-fast charging. Motorola claims both the Style and Play models will offer up to 50 per cent faster charging than even the Samsung Galaxy S6 offers, which means 35 per cent charge from a dead battery in just 15-minutes. That's streets ahead of the 2014 Moto X.

The Moto X Style has more Moto Maker options

All three Moto X smartphones offer Moto Maker personalisation options, opening up a variety of tailored options. But only the Style can deliver coated silicone rubber (soft touch), premium Horween leather and natural wood options.

Both the Style and Play will offer engraving and metallic accent options, but only the Moto X Play will be able to accept replaceable colour shells and flip shells, much like the existing Moto G and Moto E line-up.

These will add price premiums depending on your choices. Both Style and Play offer water-resistance however.

Similar software experience

One of the great things about Motorola is that it offers a more-or-less raw Android experience when it comes to software experience. There are only a few Motorola-specific apps that have been added on top so you get a very clean experience.

Both Moto X Play and Moto X Style will run on the latest version of Android 5.1.1 Lollipop, plus Motorola's new Messages app, as well as the Moto app (which allows you to use voice commands and more) added to the mix of existing Motorola apps such as Moto Migrate.

The Moto X (2014) model will eventually get these updates, however, so the software experience should be similar across all devices.

Pricing and conclusion

We think the positioning of two new Moto X smartphones is rather well placed. The Play will cost £299, while the Style, it seems, won't carry a SIM-free price in the UK (only in the US, where a specific variant will be available priced some $300-400 less than flagship competitors).

Balanced against the £420 price tag at the time of launch for the Moto X in 2014, we suspect it will be fairly balanced on contract - and less money than the flagship competitors.

It's all about choice. Big screen, big resolution, big power: go with the Moto X Style. If you want feature rich but affordable then the Moto X Play is about as good as things get, especially with its huge battery capacity.

Writing by Britta O'Boyle and Mike Lowe.