A RUSTY KNIFE AND TWO CATS

A man expertly cleans and polishes a knife he bought for $3 at a local second-hand shop as his two cats look on in apparent bemusement.

That is the premise of the top trending video on YouTube in the past week.

Since it was uploaded on June 19, the four-minute-long "Polishing A Rusty Knife" video, by the channel JunsKitchen, has gone viral, racking up close to nine million views.

Jun, who stars in the video, starts by saying he believed he was duped into overpaying for the rusty blade.

Determined to make the best of the situation, he takes out his various knife-cleaning mixtures and tools and starts the sharpening process. Soon, he uses the sharpened knife to effortlessly slice through things like paper, a leaf floating on water and a tomato in mid-air, and to create a flower out of daikon radish.

Throughout the video, his cats are seen looking on with an apparent mix of interest and nonchalance.

On Reddit, many users attribute the video's success to its simplicity, pace and overarching narrative of recycling an old product into something new and usable.

The most successful producers of viral content study trends to learn what kinds of articles and videos have received the most views and "shares" in the past, then capitalise on them, says Mr Emerson Spartz, the CEO of digital company Dose, in a Forbes article earlier this year. "Almost everything you see that's viral has already been on the Internet before. The same things go viral over, and over, and over again," Mr Spartz says.

So it's not surprising that Jun's latest viral hit is a lovechild of his two most popular videos, each with more than four millions views.

One features Jun sharpening a $1 knife while the other shows him preparing homemade cat food and comparing it with store-bought ones in front of his feline friend.

SELECTING THAT PERFECT PHOTO

Having difficulty identifying that perfect photo to upload on social media? An app - EyeEm - has released a new feature that might make that choice a little easier.

EyeEm is a stock photo service which boasts more than 20 million users. Users upload their photos and sell them on an online marketplace to any brand or customer registered with the app.

A feature, called Selects, appears above the camera roll for Android users. Utilising image-recognising technology, the app is able to tap the expertise of professional photographers via an algorithm and pick the top few noteworthy photos.

"To find your best photos, the EyeEm app scans your entire camera roll and selects the photos with the best aesthetics - pictures that are composed particularly well, have the best quality, or highest chance of selling on EyeEm Market," said the developer in a press statement released on Thursday.

Essentially, it means photos you've long forgotten about have a second chance at being posted. "EyeEm Selects… unearths the hidden gems among your photos. Chances are, your camera roll is full of pictures you didn't share right after shooting them," the statement adds.

The selection takes place on your device, the developer says.

The key feature, it adds, saves data, battery power and increases privacy as no one would be able to see the photos in the camera roll before posting.

PLASTIC SURGERY APPS, GAMES

The cosmetic procedure industry has grown significantly in the past decade in Britain, and social media is behind it, says a recent report.

The authors of the survey by the Nuffield Council on Bioethics say young people are turning to botox and dermal fillers due to online pressure.

It adds that makeover apps and online plastic surgery games aimed at children as young as nine are also contributing to a growing anxiety over body image.

"We've been shocked by some of the evidence we've seen, including makeover apps and cosmetic surgery 'games' that target young girls," says Professor Jeanette Edwards, who chaired the council's inquiry into ethical issues surrounding cosmetic procedures.

"There is a daily bombardment from advertising and through social media channels like Facebook, Instagram and Snapchat, that relentlessly promote unrealistic and often discriminatory messages on how people, especially girls and women, 'should' look," she tells the BBC.

Makeover apps like Plastic Surgery Princess, Little Skin Doctor and Pimp My Face might even be contributing to mental health problems in young people, the report added.

A British government spokesman said action had already been taken to improve regulation.

"This report highlights once again that we live in a world where young people are under immense pressure on a daily basis about how they should look," he added.

"It is ethically wrong for companies to exploit this and offer unnecessary cosmetic procedures to under 18s."