An expert has revealed five warning signs that might indicate someone is spying on you through your phone.
Tech expert and CEO of QR Code Generator Marc Porcar, from Spain, said there are multiple ways to check whether someone has installed monitoring software on a device.
Revealing the five red flags to watch out for, Marc told The Sun that seemingly ‘normal’ phone annoyances can actually be something more sinister.
The first tell-tale sign is when phone users notice their battery draining at an alarming or unusually rapid rate.
If one’s phone no longer lasts the full duration of the day but has been used as normal, this could be a sign that there’s an underlying monitoring software depleting the battery.
This is because these types of software run constantly in the background, requiring continuous connection to send data to third-party servers.
Since this requires a significant amount of battery to run, users with spyware will often notice that their battery is slurped up at a faster rate.
It may seem perfectly normal for phones to overheat at times, particularly during the summer months, but according to the tech specialist, this could be another indication of foul play.

An expert has revealed five warning signs that might indicate your partner is spying on you through your phone (stock image)
‘Phones become hot when spy applications consume processing resources,’ he cautioned.
Another key factor to look out for is when a device doesn’t cool down – despite it not being used by its owner.
Marc warned that users should be suspicious in instances where their device remains warm to the touch, even after long periods of being idle.
This can happen when devices are under additional strain from spyware, which forces their internal processors to work harder than they would under normal circumstances.
‘The temperature increase is in most cases a direct result of unauthorised background processes running on your phone,’ the expert explained.
Next on the list was an inordinate increase in data consumption because this could be a sign that there is hidden software depleting the phone’s memory.
He urged people to check data usage statistics in their phone’s settings app because this may uncover the culprit behind the increase in data usage.
Monitoring apps must send collected information to their controllers, which requires the internet to send over information and, in turn, can drive data usage through the roof.

Marc Porcar, CEO of QR Code Generator, said there are a number of signs that might suggest a device has an installed monitoring software (stock image)
‘These applications will show up as consuming data in the background sometimes using substantial amounts if they’re sending images or recording audio,’ Marc explained.
The expert said this warning sign is often the first detected by victims unwittingly subjected to spy software, with many left perplexed by texts warning them they are nearly out of data.
Next, he alerted phone users to SMS messages that contained odd or unusual characters.
Some of the more basic spyware will rely on using codes to pass over information, which can come through as unusual characters.
Lastly, he warned phone users to act with caution when they notice unusual activity from the phone when it’s not in use.
This can include a myriad of oddities, such as the screen lighting up when not in use or strange sounds coming from the phone during a call.
Marc explained that this can happen when more sophisticated spyware is in use because it can allow the culprit on the other side to access microphones and cameras without the victim’s knowledge.
Those who have sneakily installed spyware can listen to their partner’s conversations or watch them through their camera.
To minimise the chances of being spied on, Marc recommended performing regular security checks and removing unrecognised applications where possible.
As always, using strong passwords can also provide a barrier to pesky spies being able to install software in the first place, he added.
Finally, he said that users could use a full reset as a last resort to remove most types of spyware.
According to UK law, unauthorised surveillance of another person’s device is a criminal offence under the Computer Misuse Act, with penalties including imprisonment in the most serious cases.