Google launched its Google+ initiative in June 2011: part standalone social network and part social layer for existing services like Gmail and YouTube and its search engine. A year later, how has it done?

In April 2012, the company announced that "more than 170 million people have upgraded to Google+" – carefully-chosen words amid criticism that while people are enabling Google+ in their tens of millions, many less are actively using the standalone social networking part.

I sat down with Google's vice president of product Bradley Horowitz, in the UK for the LeWeb London conference, to dig into what Google+ is for, what impact it's really having, and how it might evolve.

Horowitz stresses the two-pronged nature of Google+, and the idea of the social layer as a way for "users to upgrade their relationship with Google". But what does that mean?

"People have had a pretty ephemeral relationship with Google: they typed in their query, hit enter and we sent them on their way. It was a pretty light touch, and we don't know a whole lot about those users," he says.

"If we get to know our users – have them introduce themselves: 'I'm Jeremy, I'm living in this zip code, I have these friends and these interests…' – we can provide an amazing quality of service. A better phone, better browser, better YouTube, better Gmail… Everything will get better if we understand our users better."

This hasn't historically been the corporate strategy, of course. Sending users on their way as quickly as possible was the reason Google's search engine first came to prominence.

"We've gone 10-plus years not really developing the infrastructure that would allow users to declare who they know and what they care about," says Horowitz.

Google+ is the company's big bet on making up for this lost time, along with that standalone social network element. Late to the party given Facebook's 900m+ users, Google is hoping features like its Circles for easier privacy; Hangouts for video chatting and its recently-revamped mobile app will make it a contender.

Back to the stats, though. "170m users have upgraded their Google relationship into a Google+ account – it's quite a lot more than that, but I will let our CEO announce that when he's ready," says Horowitz, who goes on to refer to "several hundred million users" having made this step.

"How is our social network doing? We're seeing record-setting days every time we look at the graphs and metrics, and the launch of our mobile apps has driven huge amounts of mobile usage and engagement."

Waiting for metrics

This is the problem for an outsider trying to judge the success of Google+ so far. The key metrics are clear for its social network – number of active users, and how active those users are – but Google is keeping those to itself. Unsurprising, given the inevitable comparisons with Facebook.

But the success of Google+ as a social layer across all of Google's services is harder to define. Are people finding more relevant search results? Sharing more YouTube videos? Using Circles as a key filter in their Gmail? "We're not sharing that level of metrics," says Horowitz.

Another area of scrutiny for Google+ has been its status as a platform for developers. With applications a key element in the growth of Facebook, you might imagine the pressure is on for Google to catch up on the APIs side of things. Google itself is resisting that pressure.

"We have been very thoughtful and deliberate in how we have rolled out our APIs," says Horowitz. "We have been working with a handful of named partners to learn what they want in the APIs, and to learn how users react to the content sharing using those APIs."

The latest partner is Flipboard, announced at LeWeb London. Horowitz says Google+ integration was the "number one most-requested feature" for the personalised magazine app, and praises its deep integration, which goes beyond just a button to share articles to Google+.

"It's another step in our journey of being more open with the APIs that we're creating," he says. However, Google is also portraying this slow-but-steady rollout as a contrast to Facebook, and some of the challenges that social network has faced in balancing the interests of developers and users.

"One factor is doing right by users," he says. "Sometimes the agendas of an application developer might be misaligned with the agenda of users. A game might want to get viral, explosive distribution and reach as broad an audience as possible, but some users might find these efforts annoying – or worse, spam."

Is being more cautious about its API rollout the best way for Google to maintain a balance between these interests: developers looking for distribution and users trying to control their streams? Horowitz hopes that safeguards in Google+ will succeed where Facebook has occasionally run into difficulties.

"They're not necessarily at odds: they just need to be put in balance, but we have seen from our competitors in the market that it's very easy to get these ecosystems wrong" he says.

"Changing the rules about how these systems work, or yanking developers around is very annoying and unfair to them. We want to ensure we roll it out in a way that's not only good for users, but for developers. Unfortunately that means asking most of them to wait for now."

More friction, not less

While on the subject of signal-to-noise ratio in social network streams, what about frictionless sharing? It's a key part of how Facebook sees its users interacting with applications and external services, but it's also sparked lots of debate about over-sharing.

Is sharing every song streamed / movie played / meal cooked / etc in Google+'s future?

"Friction can be a very good thing. We've introduced quite a bit of friction on our system," says Horowitz, noting that to share something on Google+ requires specifying which Circles to share it with.

"That moment of pause gives people the security of ensuring that their privacy isn't violated. We think that's the trade-off people want: considered, thoughtful and authentic, as opposed to everything shown to the least common denominator of 'public'."

He goes on. "We've introduced friction into the system as a design constraint that forces people to be thoughtful and considered. As a philosophy, it's unique."

The final area of discussion with Horowitz concerns mobile – hugely important for Facebook and Twitter already, and clearly high on Google's agenda for Google+ too.

The redesigned mobile apps have been widely praised for their striking design – not traditionally seen as a strength for the company – while features that were missing from the initial versions like Hangouts have been added quickly.

A question about Apple's integration of Facebook in iOS 6, and how Google might tie Google+ deeper into its own Android OS in response, leads Horowitz to talk instead about Google's commitment to iOS itself.

"iOS is a hugely successful platform, users want us there, so we'll be there. But that's not at the expense of having an incredibly awesome and great Android experience. There is more work to be done there, but nothing specific to announce at this stage."

Earlier comments about how smartphones should work hint at Google's determination to make Google+ a critical part of Android, however.

"My phone should understand Circles, and it should know that if my wife calls me, the phone should ring at any hour, but if a headhunter or someone who's not in a Circle calls, send the straight to voicemail," he says.

In the meantime, more features will debut in the Google+ mobile apps, rather than the web version. One example already is the ability for a user to choose to see only Google+ posts from their surrounding area, but more will follow.

"Increasingly as we see usage of mobile skyrocket, the proposition of mobile-first – developing features first or exclusively on mobile – becomes even more viable," he says. "It's where our users and usage is. You will see us really double down on mobile… We're good listeners at Google, and we have the advantage of a very vocal base."