A number of third-party cases designed to fit the upcoming Samsung Galaxy S IV have been obtained by British accessory retailer MobileFun. Made by a “trusted” Chinese manufacturer, the cases give us an idea of the size and shape of Samsung’s much-anticipated flagship, which looks to be nowhere near as curvy as its predecessor.

There are four cases in total, all of which have clearly been manufactured using the same dimensions. They suggest the Galaxy S IV will look more like the Galaxy S II or the Galaxy Note rather than the Galaxy S III, with a relatively square form factor and slightly sharper corners. They actually look like they could fit that purported press image that leaked last month.

It appears the device will be bigger than its predecessor, which fits recent rumors that have suggested the device will pack a 4.99-inch 1080p display. The rear-facing camera sits in the same place — in the center of the device — but the case’s camera cutout suggests it will have a larger lens.

There are also cutouts either side of the camera, which are likely to be for the LED flash and the speaker. Like most Samsung handsets, there are volume keys on the left side and a sleep/wake button on the right, plus a headphone jack on the top edge and a micro-USB port on the bottom.

Of course, third-party cases — particularly those that come from unknown brands, like these ones — should always be taken with a pinch of salt. While some companies do sometimes provide accessory manufacturers with details on upcoming products in advance, they’re much more coy when it comes to major products like this.

And when they do provide details in advance, they usually only go to large, trusted manufacturers with big brands.

So where do these cases come from? Well, sometimes, case manufacturers read the same rumors you and I do, then they make cases based on what they’ve heard in the hope that the rumors are accurate — and that they’re then one of the first to market with their cases.

With that being the case, I wouldn’t bet on these too much until Samsung unveils the real thing, which is expected to happen on March 14.

• SourceMobileFun