It's an app that claims to be for "capturing and sharing the world's moments". But in early April astronaut Steven Swanson, aboard the International Space Station, uploaded the very first Instagram photo posted from out of this world.
No prizes for guessing that Swanson was the star of a unique selfie. In orbit, as on the surface of the planet, the selfie - or self-portrait, as it used to be known - is fast becoming a defining feature of global culture. Do you know anyone with a smartphone who's never shared a selfie?
Selfies are now so common on social media that they've often become controversial; the White House is thinking of banning all selfies with President Barack Obama after a recent snap with baseball player David Ortiz was tweeted by his sponsor Samsung. It went viral.
The selfie has lost its innocence, and is fast becoming shorthand for any photo of people that has been taken with a smartphone, but the casual self-portrait refuses to lose its mass-appeal. You might not have planet earth as your backdrop, or a president by your side, but taking better selfies is now a core photography skill.
Luckily, there is plenty of advice and lots of gadgets to give us a hand, chief of which is the aptly named #The Selfie (HK$148, amazon.com Designed to make taking a selfie less awkward, it has a remote trigger on the grip that operates the shutter release within the camera app, Instagram or Snapchat on the iPhone and iPad, which it attaches to via the headphones slot.
You might feel a little self-conscious while using it, but it ought to help you avoid the common error of not looking - or, worse, appearing distracted and confused - at the camera lens while taking a selfie.
Also replacing the smartphone's touch screen shutter button is Muku Shuttr (HK$310, mukulabs.com This is a selfie remote that uses Bluetooth to command Android and iOS devices wirelessly.
A steady shot and hands-free control are nothing without some resolution. The front-facing camera on your current smartphone will do fine, but for how long will two-megapixel selfies suffice?
Stay ahead of the curve with the new HTC One (M8) (HK$5,998, htc.com/hk-en; the smartphone of the moment has a selfie-centric five-megapixel front-facing camera purely for improved selfies.
An even higher resolution option is the Samsung NX Mini (HK$3,290, samsung.com/hk connected compact camera, which not only manages 21-megapixel selfies, but also features an 180-degree flip-up, three-inch "hatchback" touch screen display that's designed only for selfies.
It gets better, promising hands-free selfies by winking. Facial recognition software sees the wink and takes a photo two seconds later. The NX Mini also has Wi-fi and shares selfies with Flickr and Dropbox.
But before you do that, some careful editing might be in order. Photo-editing apps help get the tone right, or just liven it up with some bright colours, but some go even further.
VSCO Cam is great for editing Instagram pictures, while Facetune has just been launched for the iPad and promises Photoshop-style results. We're talking filters that improve your skin, and even your bone structure.
Structure of a different kind is offered by Picr, which uses daily reminders to help you create a selfie journal.
But the best selfie app yet is Shuttersong, which lets you add 15 seconds of audio before posting your selfie; either some music or your own voice-over. It was only a matter of time until the selfie learned to talk.