Last April, I took a look at the products that Twitter staff members were using to send their tweets, publishing the results on our sister blog, Social Times. Back then, some 85 percent of all tweets from Twitter employees came via official Twitter products, with 32 percent of those from Twitter.com.

Fast-forward almost a year later, and Twitter’s stranglehold on how its employees tweet has increased – a heady 94 percent of all staff tweets now come from official Twitter products.

There’s never been any official word on whether the Twitter team has complete carte blanche on which products they can use to update their Twitter profiles. We don’t (and likely never will) know if  third party apps are encouraged, allowed, outright banned or simply frowned upon. But as Twitter has tightened the reins on its ecosystem and started buying out competitors, their position on this has become less important, simply because there are fewer (credible) alternatives available.

Here’s last year’s pie chart.

And here’s how that data looks today, courtesy of updated figures from Twitter’s Isaac Hepworth.

Twitter.com still dominates, at 35 percent of all tweets, ahead of Twitter for iPhone and Twitter for Mac. The first seven products are all official Twitter clients.

Instagram is the most-used third party service, in the eighth spot, ahead of Tweetbot and the iOS camera (which, thanks to the IOS 5 Twitter integration, is also kind of official).

It’s worth noting the lack of any dashboard-style Twitter applications in this list, such as HootSuite or CoTweet, which reminds us of the ‘nifty features’ available to Twitter employees that former Twitter lead engineer Alex Payne was talking about way back in 2010.

Must be nice to be part of that inner circle. You have to wonder if a product like HootSuite is either unnecessary to Twitter employees, because of what they have available (that the rest of us do not), or is simply not allowed.

Of course, there’s an obvious business model here that Twitter isn’t leveraging, and that’s a premium, billable Twitter dashboard for brands and power users. And when you consider that they’re still struggling to turn a profit, you have to wonder why.

(Hat tip: The Next Web.)