Google Glass is celebrated and derided in equal measure. My colleague Ashleigh was genuinely impressed by its difference and possibilities, while others see it as an unwanted intrusion to their enjoyment of the real world.

As the ’next big thing’ – or not – it certain demands people’s attention (and opinions), testing one of the first models in the UK by walking around British landmarks like St Pancras Station, Ashleigh was mobbed by enquiring passers-by – though the film crew following her may have drawn as much attention to her as the headset itself.

But anyone who says they have the definitive answer as to whether Google Glass is good or not – or will be a success or not – is talking nonsense. Glass is still a prototype for good reason – no-one knows whether it’ll be useful for a small group of people or everyone-and-their-mum. The hardware exists either in 80s sci-fi B-movie prop form or as high-fashion glasses only a tiny subset of young, good-looking people could pull off – but the apps and services that may or may not turn it into something useful are still to come.

When the iPhone was first launched, did we think its primary purpose would be for us not to make calls and send email, but to do a thousands tasks using apps tailored for the many to the few: from the apps everyone uses like Facebook and Twitter to those innovative digital services that make a big difference to a smaller audience from Citymapper to Evernote to Rev.

The same is likely true for Google Glass. If there’s a killer app that’ll make it indispensable for you, chances are it doesn’t exist yet – but here are a few people I could see it being very popular with.

Google Glass for Surgeons

Surgeons need to keep their hands free – and sterile. I could imagine a voice-controlled tool in constant field of view - providing information wherever a surgeon is looking – could be a major boon. Plus you can easily record what you can see for review later – which could be helpful for improving surgical procedures. But then it could also be a constant distraction in a highly-skilled task that requires focus.

Google Glass for Extreme Sports

This is an example Google has already shown. Again, the idea that you can gain information and record your crazy exploits while keeping both hands free will be useful to extreme mountain-bikers and skydivers – but again the information might be a distraction from the important tasking of not riding off that mountain, and most people who record their extreme sports adventures seem quite happy to strap a GoPro to their head.

Google Glass for the Police

The idea of the Police recording everything they see and hear has gained popularity even with civil liberties campaigners once it became apparent that it helps prevent abusive behaviour from offices as well as collecting evidence. It’s also easy to see where the information Glass provides directly in front of an office would be useful – providing everything from background information on addresses or potential suspects while talking to them to in-view navigation while chasing suspects through backstreets.

But will a Glass be resilient enough to withstand the daily beat? Or being hit by a flailing drunken muppet?

These aren’t everyday examples, but I can see how Glass could be developed in these specific directions and tailored for their needs – for example, switching its screen on and off caused by different head motions. Different versions could be developed for different needs or – as with the iPhone – apps and accessories could add different functionality, or conversely we could see Glass technology incorporated into other hardware. A function of something rather than it’s core.

Currently the future of Google Glass is more full of questions than answers – but it’ll be an interesting journey to follow.