Sony is no stranger to the launch of new devices. No sooner does one smartphone hit the shelves, than another swiftly appears to expand the portfolio yet again.

Two new mid-range devices were announced this week, comprising the Xperia M5 and a 6-inch smartphone with a big focus on selfies - the Xperia C5 Ultra. They join the Xperia Z3+ flagship that arrived just a couple of months ago and the M4 Aqua, which was only unveiled at Mobile World Congress in March. Confused yet?

We have put the Xperia C5 Ultra up against the Xperia Z3+ to find out what the differences are between Sony's latest flagship and its latest smartphone addition, and whether there is a case for choosing the C5 Ultra over the Xperia Z3+, despite it opting for lower-end specs.

The Xperia C5 Ultra measures 164.2 x 79.6mm while the Xperia Z3+ is only 146.3 x 71.9mm so significantly smaller. The Xperia Z3+ is also slimmer and lighter at 6.9mm compared to 8.2mm and 144g compared to 187g.

You can tell Sony has followed similar design cues as its Z series, but the similarities between the C5 Ultra and the Z3+ are nowhere near as close as the M5 and the Z3+. The signature power button and rounded edges are still present, but the rear camera moves from the left to the centre for the C5 Ultra, while the front camera is on the right instead of the left. The C5 Ultra is also less of a flat rectangular slab, with its rear panel protruding slightly - hence the extra thickness.

The Xperia C5 Ultra comes in black, white and a mint green, while the Xperia Z3+ is available in black, white, bronze and aqua green.

The Xperia C5 Ultra has a 6-inch display, compared to the 5.2-inch display found on the Xperia Z3+. Both offer the same 1920 x 1080 resolution though, so the Xperia Z3+ will have sharper, crisper images.

The C5 Ultra has a pixel density of 367ppi, while the Xperia Z3+ packs in 424ppi. The C5 Ultra has quite a low pixel density for a display of this size, with competing devices such as the Nexus 6 opting for a QHD resolution.

Both are IPS displays but the Xperia Z3+ offers other Sony technology including Triluminos and X-Reality, which should give the colours and brightness of the Z3+ a little more punch in comparison to the C5 Ultra.

The Xperia C5 Ultra features a 13-megapixel rear camera that offers 4x digital zoom and 1080p video recording. The Xperia Z3+ on the other hand has a 20.7-megapixel rear snapper with 8x digital zoom and 4K video recording, so on paper, the flagship wins here.

In terms of the front-facing snapper however, the Xperia C5 Ultra has a 13-megapixel camera, while the Xperia Z3+ settles for a 5-megapixel sensor. Both have a wide-angle lens, but Sony has also added a flash to the C5 Ultra, along with 4x digital zoom.

Both the C5 Ultra and the Z3+ are capable of 1080p video recording from their front-facing snappers.

The Xperia C5 Ultra arrives with a 1.7GHz octa-core MediaTek chip under its hood, supported by 2GB of RAM. The Xperia Z3+ has 3GB of RAM support, along with the octa-core Qualcomm Snapdragon 810 processor, which is made up of a 2GHz quad-core chip and a 1.5GHz quad-core chip.

In terms of storage, the C5 Ultra has 16GB of internal storage with microSD support for up to 200GB, while the Xperia Z3+ has 32GB of memory and microSD support for up to 128GB.

Both the Xperia C5 Ultra and the Xperia Z3+ have the same battery capacity at 2930mAh, but it is worth bearing in mind that the new handset has a bigger display to power.

The software experience on the Xperia C5 Ultra and the Xperia Z3+ will be similar in that they both run on Android Lollipop with Sony's overlay on top, but there are a couple of differences.

The flagship Xperia Z3+ offers extra features such as hi-res audio compatibility, as well as DSEE HX, which is the ability to upscale music to nearly hi-res quality. The Xperia Z3+ also comes with PS4 Remote Play, which allows users with a PS4 to play their console games on their smartphone.

Although the Xperia C5 Ultra won't offer the features mentioned above, it will still offer Sony's plethora of entertainment apps, including Walkman and Movies, as well as Xperia Lounge.

The Xperia C5 Ultra is nowhere near flagship in terms of specs, but it offers a large display and a big focus on the front camera so it may appeal to some regardless.

The Xperia Z3+ is smaller, lighter, offers a sharper display, more internal storage and a more powerful processor. That said, it is likely to be more expensive than the Xperia C5 Ultra, and for those that want the big display, the Xperia Z3+ might just not cut it.

The Xperia C5 Ultra wins on the front-facing camera, while the Xperia Z3+ gains points back on the rear snapper, but both are on par when it comes to battery capacity.

Ultimately, although the Xperia Z3+ has the better of the specs, the Xperia C5 Ultra might be just what some people are looking for - if the price is right.