Google and Facebook are, of course, not the only apps tapping into the functionality lying dormant in every smartphone.

Mobile app developer Matthew Moulin, who works at Flipmind, recently wrote to the Herald expressing concern about a locally produced app's use of the camera on his phone.

While watching TV, with his phone sitting on the coffee table, he noticed an alert notification light up on the screen.

"I opened it to see that [the app] was trying to use my camera in the background. In fact, it has been doing this consistently every few days," he said.

Concerned, Moulin put his app development skills to work and downloaded the back-end file, which features a rundown of all the permissions the app has historically activated.

He was alarmed to discover his camera had been activated numerous times in May, despite the fact it wasn't until June 2 when he first gave the app permission to use the feature to scan a barcode on a store-bought item.

Moulin said this may well just be a glitch in the design of the app, but expressed concern about what the camera captured while it was activated and where this recording ended up.

The problem with digital tech is that it has capitalised on our ingrained behaviour of agreeing to terms and conditions without reading them. And the horror of this only shows its face when things go wrong.

It is analogous to buying a lemon from a car dealer. Even if we lift the hood and have a look inside, there's no guarantee we're going to spot the problems in the moment.

We'll only realise we've made a mistake in agreeing to the terms and conditions when we end up in a collision with the next big data scandal.

In this sense, every app on our mobile phone is a potential lemon. And the only question that remains is how much the lemons we bought today will cost us in the future.

How to protect your data:

Cyber security expert Peter Bailey, the general manager at Aura Information Security, says it's impossible to protect your data completely if you're using a mobile phone but recommends users stay vigilant in the following ways.

• Do your homework if you are going to share your location information. Decent websites should give you access to the company's privacy policy, telling you what they are doing with your data. Always read the terms and conditions so that you know what you are agreeing to.

• While there was some intention a few years ago for apps to be developed with "privacy by design", this isn't closely monitored. Many apps may leak location data, and users should therefore check their own cell phone settings – both for the phone in general and each app.

• Try not to enable location services unless you really need them, and think carefully about who is getting this information. Now that you are aware, you may be able to prevent some unauthorised use of your location data.

- Additional reporting from the Daily Mail.