US researchers have created a new smartphone device that can analyse a man's sperm quality. In just a few minutes, the device can determine whether a man suffers from infertility - with an accuracy of 98 per cent.

It works by using a combination of an optical attachment that can connect to a smartphone and a disposable device for loading a semen sample.

Here are five other mind-blowing things your smartphone can do:

1. Listen in on what other people are saying

An app called Ear Spy amplifies sounds coming through your phone microphone straight to your earphones, enabling you to listen in on people's conversation in the next room.

While the app has been touted as the "Ultimate Eavesdropping Tool" on its Google Play Store page, users, nonetheless, should scroll all the way down the page to read the disclaimer before attempting to use the app for anything illegal.

2. Tell you if your food has gone bad

In 2014, chemists at the Massachusetts Institute of Technology (MIT) devised a way to wirelessly detect hazardous gases and environmental pollutants using a simple sensor that can be read by - what else - your smartphone.

The sensor is able to detect ammonia, which is the source of the odour when your food has gone bad.

3. Send long-distance kisses

Video-conferencing apps like Skype and Facetime have almost rendered the long-distance phone call obsolete, as people can now see their loved ones on top of hearing them.

By 2019, you may be able to kiss your loved ones through your smartphone with a device jointly developed by scientists in Britain and Japan.

These mouthpieces can replicate your partner's kissing motion including tongue motion. The device is designed like a phone cover that plugs into the audio jack of an iPhone or iPad.

The accompanying Kissenger app is actually not too different from today's messaging apps, except that instead of a kiss emoji you will be able to send the real thing... Well almost.

4. Assess your mental health

Dartmouth University researchers created an Android app in 2014 that automatically measures sleep duration, number and length of conversations per day, physical activity, time spent at various locations, stress level, eating habits and more - and then crunches all the data to provide an assessment of your mental health.

5. Record where you have done your "business"

Users get exactly what they ask for with Places I've Pooped: an app that allows them to document every place they have pooped in, and give each location a rating to boot.

Places I've Pooped also has a social element. Users can share their locations on Facebook and also follow their friends to see where they have pooped.

Sources: Daily Mirror, mentalfloss.com