If you want more friends to like or comment on your photos, researchers suggest that you pick filters wisely.

Instagram, one of the best-known photo-sharing apps, lets users apply various filters to change the look of digital pictures.

From Valencia to EarlyBird, Instagram filters tweak everything from contrast to colour balance with easy presets.

Other camera and social media apps also feature filters designed to spruce up the look of smartphone photos.

The tinkering that might take professional editors ages on Photoshop is just a tap on mobile devices.

But are filters frivolous attempts to disguise blemishes or a tool to boost engagement?

The science behind filters

Researchers from Yahoo (which owns the photo-sharing platform Flickr) analyzed 7.6 million public photos posted using the Flickr app.

They found filtered photos are 21 per cent more likely to be viewed and 45 per cent more likely to be commented on.

In a Tumblr post, researchers Saeideh Bakhshi and David A. Shamma said that the type of filter used could further affect feedback.

And you may want to think twice when it comes to deciding between a light, overexposed filter or a dark, ominous effect for that selfie. Photos with warmer colours are more likely to elicit comments or likes, along with pictures that have higher contrast and correct exposure.

Missing out on Instagram?

Speaking of engagement on social networks, Instagram appears to be reminding some users of what they’re missing out on.

According to TechCrunch, the social network owned by Facebook is sending emails to some users. In the emails, Instagram touts select photos from contacts as “highlights.”

This could be a sign that Instagram is trying to revive interest from users that are no longer active on the platform.

If you were to listen to a 15-year-old from Australia, teens think Instagram is “over” and have moved on to Snapchat.