This has been something of a hot potato in forums and discussions. I refer to Windows 10 Mobile being in 'beta' and I get shouted down that Microsoft has been officially selling the Lumia 950, 950 XL and 550 for months now, with the OS on board and nowhere in the documentation or interface does it mention 'beta' or anything like it. Then, however much I enjoy using Windows 10 Mobile (and think it's the future), I point to numerous features which simply don't work yet, screens that freeze or apps that crash and say 'Well, it behaves like a beta to me'... Of course, it all depends on how you define the term 'beta' - of which I offer some thoughts below.

Are the pedants right? No. Traditionally, 'beta testing' is defined as:

'a trial of machinery, software or other products in the final stages of development, carried out by a party unconnected with the development process'

I have to say that this sounds EXACTLY like the Windows Insider programme that most people reading AAWP have been using for the best part of a year. We've been trialling, testing and giving feedback on Windows 10 Mobile 'Threshold' (the '10586 branch of the code), the releases are still rolling out on a weekly or fortnightly basis and there's still no sign of a production version that can roll out to the great unwashed, the tens of millions of users of Windows Phone 8.1. When these people get offered W10M then I'll consider the beta testing programme for the OS 'over'.

Or at least as 'over' as 'Windows 10 as a service' can be - the idea is that, just as with desktop PCs and laptops, patches and updates can thereafter be sent across ad infinitum, with the phones being kept constantly up to date. Which is admirable. We just haven't gotten to the starting line yet. For regular users at least.

I'm very used to testing beta software, to finding bugs and inconsistencies and then reporting them to the developer, ideally with a blow by blow account of how to recreate the problem. And, again, this is exactly what we've been doing via the 'Windows Feedback' application. The Lumia 950 and 950 XL boxes may not say 'this phone contains a beta OS that will be finished over the next few months, so bear with us and enjoy being the first to use Windows 10 Mobile' - but they really should.

As the main writer for All About Windows Phone, I have my own 'watch list' of issues, problems and applications that I'm waiting to see fixed or filled in. Then, when something changes at Microsoft's and, or in the Store, I can swoop in and write the appropriate 'XX has arrived or been fixed' story. My watch list currently overflows a side of A4, fairly tightly written - and those don't include niggling bugs (e.g. the Settings pane freezing and having to be aborted via the multitasking carousel). My watch list is for long awaited universal applications, features which were promised months ago and which still haven't arrived, and issues which are serious enough to be showstoppers (e.g. Messaging+Skype running away with a phone's battery).

Now, it's not a cardinal sin to be in 'beta' for ages - look at Gmail, one of the most successful Internet services of all time and used by almost everyone, yet it was in 'beta' for well over five years. Ditto Google Maps. So we shouldn't apply too much stigma to the term. If anything, 'beta' means that the programmers know full well that there are still problems and that they're actively trying to fix them - which has to be a good thing.

It does seem as though we're nearing the end of the Windows 10 Mobile 'Threshold' beta though - we saw recently the split of the Insider rings, with 'Fast' and 'Slow' diverting brave souls off into the next-generation 'Redstone' branch of the OS, tying even more closely into the current code for Windows 10 on the desktop. Redstone isn't scheduled to hit mobile until well into the summer.

The remaining Insider ring was 'Release Preview'. Hang on.... 'Preview'? I thought the pedants were decrying my 'beta' labelling? Isn't 'preview' effectively a synonym for 'beta'? In fact, in a traditional software development cycle, 'Preview' comes before 'Beta'. So I'd release AAWP v0.1 as a 'preview' app, giving people an idea of what it might do, then this would transition, version on version, into AAWP v0.5, 0.6, and so on, all labelled as 'betas', and then finally we'd get to the big AAWP v1.0 release, at which point it would be out of beta.

These are just words though - I doubt very much that 'Release Preview' will make way for something with the word 'beta' in the title in this case. Thankfully.

What does the future hold for Windows 10 Mobile versioning and status? Here's my best guess:

• Early March 2016 - final Insider builds on the Threshold (10586) branch
• Mid March 2016 - release of a production-ready build to all current W10M-native devices (e.g. Lumia 950) and to a few test WP8-native Lumias - the 640 and 640 XL are favourite here
• End March 2016 - more WP8 Lumias get the 'final' build, the Lumia 535, 830, 735 and 930 probably.
• Early April 2016 - newer Threshold builds appear on Insiders, fixing smaller bugs and issues
• Mid April 2016 - possibly the 'final' Threshold version is released over the air to all W10-native phones and to all the older Lumias mentioned above. 
• May 2016 - a few more Lumias are added to the update availability list, but also a statement comes out (quietly) from Microsoft that due to a desire to keep the user experience fast and fluid, Windows 10 Mobile will not now come to many of the older Windows Phones, including the 520, 620, 920, 925 and 1020. Well, I told you so.
• July 2016 - the Redstone branch of Windows 10 Mobile has been chugging along with releases for Insiders and this starts to now be pushed to production W10-native devices (e.g. 950)

Comments welcome, of course. The timeline above is just a guess, a work of fiction, but hopefully realistic too. Although it's disappointing to see everything proceeding more slowly than everyone had hoped, you should also not underestimate the complexity of these operating systems. Over in the Android world, version 6 (Marshmallow) was announced almost a year ago, and it's only just got over 1% uptake, i.e. 99% of Android users still use an older version of the OS, thanks to the sheer complexity of all the various manufacturers tweaking, testing and rolling out v6.0. Even iOS has been plagued with issues in recent years and we've seen many bug-fix versions and uptake of the current version stall in the 70% region. Operating systems are now so complex that they're almost living entities - and prone to breakdown and problems, however minor. And as Insiders we're seeing how the sausage is made, as it were....

So yes, I think it's absolutely fair to say that Windows 10 Mobile is in 'beta', if not in name. And at least the end of the great beta test is in sight now.