(Pocket-lint) - Sony Mobile launches a lot of phones and over the past few years we've seen things run from Xperia Z, through Xperia XZ and into a numerical system, with the Xperia 1, Xperia 5 and Xperia 10. 

It was no surprise that there was no clue what the next Sony phones would be called until they were announced.

Sony had said at the launch of the Xperia 1 and the Xperia 10 that it wanted to stick to those names, with the Xperia 1 being the flagship and the Xperia 10 being the mid-ranger. That was confirmed to us at the time, but it was never clear how Sony would move things forward. Now we know. 

Borrowing from Alpha 

Sony has looked to its other product families for a solution and found it in its cameras. The Sony α or Alpha cameras sit in different segments, with the α9 at the top and the α7 slightly lower - but models are released as a mark 2 or mark 3. So you have the Sony α7 II for example.

That allows Sony to update a model, but hang on to the root name so customers generally know where it's positioned. 

That means we now have the Sony Xperia 1 mark 2 - or as it will be written Xperia 1 II. We also have the Xperia 10 II and undoubtedly in the future we'll get an Xperia 5 II.

At the moment that all seems clear, although this doesn't apply to all Sony Mobile devices. The L series, for example, has updated with the Xperia L4, the successor to the L3.

On the whole we like this new naming. You know exactly what position the phone is in and you know whether it's an older version or newer version. 

So that's it - nice, simple and hopefully not too confusing.

Writing by Chris Hall.