Smartphone users, it isn't just Big Brother who may be watching you; so could your boss, your parents and even your spouse.

With the growing use of smartphones and availability of apps that track your communication and movements, it's no wonder agencies like Communications Security Establishment Canada and the U.S. National Security Agency may be monitoring your phone activity; but for less than $20 a month, so can your partner.

What are spy apps?
Spy apps like Spyera, Stealth Genie and mSpy allow users to access information on a targeted phone in real time. Users can track a person's call history, read text messages and emails, monitor social media interactions, and see photos, videos, browsing history and calendar activities, all while the phone is in the palm of the owner's hand. Even more terrifying, some spy apps allow users to track the owner's movements, listen in and record live conversations, and even remotely control the other person's phone from an online control panel.

Mihat Oger, creator and owner of Spyera, says its software is designed for parents to keep tabs on their children and bosses on their employees, but it's also used by individuals who suspect their partners are cheating.

"Cheating has always been, and always will be, with us. Technology simply makes it easier, or allows us to cheat with people in different locations," Oger says. "Spyera was created to bring the best mobile surveillance technology to people at prices they could afford and with the reliability that is essential when you are trying to get the truth."

Installing spy apps
While extracting information from a smartphone may be as simple as pressing a few buttons, loading the app onto the targeted phone poses a few challenges. To install spyware, the user must first get her hands on the targeted device (spy apps can't be installed remotely). Next, the phone has to be "jailbroken" (iPhone) or "rooted" (Android) so that its operating system will allow third-party software to run.

According to Oger, Spyera can be installed in the amount of time it takes to brush one's teeth or have a shower.

"It can easily be installed on an iPhone in less than 10 minutes," says Oger. "It takes nine minutes to jailbreak and one minute to install Spyera."

Once installed, a spy app has no application icon and works silently in the background, without the knowledge of the phone's owner.

Are spy apps legal and moral?
For all their high-tech sleuthing capabilities, spy apps do have one major caveat.

In Canada, use of a spy app without informing the device's owner is illegal and considered an invasion of privacy.

Tucked away in a discreet corner of Spyera's website, buried under numerous terms and conditions, lies the disclaimer: "You are required to notify the device owner that the device is being monitored."

Explains Oger: "The responsibility lies with the user to not use features that are illegal. It's much like a Ferrari — it can do 200 miles per hour, but that's up to the driver."

Aside from its questionable legality, spy apps also raise some serious moral issues.

"Trust is the foundation of every relationship. Once that starts to erode, it creates problems and the relationship begins to spiral out of control," says Floyd Spence, a marriage and family therapist in Toronto. "When the cheater starts to rebuild the relationship, he/she may develop trust issues. Is my partner still watching me? Is there a spy app on my phone? The effect of this is going to be long lasting."

Growth of spy apps and infidelity
Monitoring a partner doesn't just tax your relationship, it taxes your wallet, too.
A basic three-month mobile subscription to Stealth Genie costs $60, while one of the same duration from Spyera will set you back $189.

Despite the steep costs, Oger says the market shows no signs of slowing down; he estimates the increase in spy app users parallels the growth of smartphone usage.

According to a 2013 report by Google Canada, the number of Canadians using smartphones has risen from 33 percent in the first quarter of 2012 to 56 percent a year later.

Spy apps usage is not the only thing on the rise. According to Spence, infidelity cases have more than doubled in the past 10 years.

"Previously, cheating involved a man going off or out of town 'to work' but ended up connecting with someone else. In today's world, the Internet has literally brought sex to a person's doorstep," he says. "We find individuals engaging in cyber sex or those who have gone into chat rooms and are having sexual interactions with others through their webcams…. There's also sexting and individuals taking photographs of their private parts and sending them to other people."

Ashley Madison, the popular Toronto-based infidelity website that arranges hookups between people already in relationships, has accumulated over 25 million members worldwide since its launch in 2002. At least 1.2 million members live in Canada, with Ottawa being the most active Canadian city on the site.

Says Spence: "I don't see infidelity stopping. I see cyber infidelity increasing. People have seen things, people have developed their own fantasies of what they want and so they will go in search of that."

What should you do if you suspect your partner is cheating?
If your partner is constantly hiding his phone, taking phone calls outdoors or away from you, or regularly deleting his browser history, it could be a warning sign that he is cheating.

Spence offers four tips for handling the situation:

1. Engage your partner in a conversation
"The best way to go about this is not to be judgmental, not to draw conclusions but to ask questions," Spence says. "Use 'I' statements as opposed to 'you' statements." For example, don't say, "You are always on the computer." Instead, say "I noticed that our time has been diminished, can you help me in understanding why that is so?"

2. Ask for honesty
"It's important to let your partner know there is a pattern of behaviour and you need the truth," Spence says.

3. Speak to a professional therapist
If your partner refuses to come clean, consider hiring a professional therapist. A therapist is trained to deal with these situations and can advise you on how to deal with it and move on.

4. Think twice before you consider using a spy app
"It's unethical…. This is not something I would recommend," says Spence. "You want to be mindful that you don't violate the other person's rights and hurt the person in the process." Using spy apps only promotes mistrust and may hinder the relationship recovery farther down the road.

Dealing with an unfaithful partner takes a toll on your relationship and your emotions. Learn how you and your partner can move forward after an affair.