Parents, jealous partners and employers are being encouraged to intercept texts and phone calls using new 'spy apps.' Several companies have launched apps which give full access to smartphones or computers, allowing snoopers to see text messages, emails and photographs, listen to phone calls and even activate phones to listen to sounds around the handset even when it is not in use.
Once installed, the phone spy technology becomes 'invisible', meaning users only need to access a handset once for unlimited access.
Such surveillance is illegal in the UK except in specific circumstances such as police investigations, and even then use of such powers is strictly limited.
The Regulation of Investigatory Powers Act 2000 makes it an offence - punishable by up to two years in prison - to intentionally intercept any private communication "without lawful authority."
Additionally, the Human Rights Act 1998 states that "everyone has the right to respect for private and family life, his home and correspondence", while the Protection of Freedoms Act 2012 includes "monitoring the use by a person of the internet, email or any other form of electronic communication" in its definitions of stalking.
But makers of spy apps such as Stealth Genie, Mobistealth and Mspy market themselves as ways to protect loved ones and even employees.
All three websites include disclaimers telling customers they must get permission from phone owners before installing the software - but these are in stark contrast to their marketing, which focusses on secret surveillance.
In a promotional video on Mobistealth's website, the presenter says: "Who did your kids talk to today; not just face-to-face but using their cellphones and computers? How about the rest of your family? If you've got employees, what did they do today? How much time did they spend on Facebook, Twitter and YouTube?"
The presenter adds that everyone has important people they want to "monitor and protect."
The makers of Stealth Genie, who claim their product is for "ethical monitoring... with written consent", say the app allows users to remotely control another person's phone, letting them to delete information and even lock a phone to prevent use.
And in a video on Mspy's website, the presenter says: "Any person's cellphone can be used as a remote listening device that will spy on its owner." Speaking about this video, cyber-stalking expert Jennifer Perry said: "It is so outrageous, if it wasn't a real product it might be funny." Mrs Perry, who runs www.digital-stalking.com to help victims, said such technology is commonly used by stalkers.
She said: "If I have a stalking victim I always assume that they have spyware on the computer and, if the perpetrator had access to the phone, the mobile." Mrs Perry added she has also come across cases of parents installing the technology on their children's phones to spy on ex partners.
Some spying programmes can currently be installed on PCs 'remotely[ (without physical access to the computer) but at present such software can only be added to phones by holding the handset, Mrs Perry said. But she added: "I fully expect remote installation of spyware, like we have on the PC, to be available on phones - probably by the end of the year."
The spy apps are not available in the App Store on iPhones, and most 'tracker' apps - which claim to allow users to locate other smart phones without the owner's consent - do not work.
For advice on what to do if you suspect spy software is affecting your computer or mobile phone, visit www.digital-stalking.com or call the National Stalking Helpline on 0808 8020300.
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