​Do companies have a right to watch employees 24/7?

Some employers may be making it impossible to get away from the job.

That's what one California worker is alleging in a lawsuit, claiming that her former employer, a money transfer service called Intermex, installed an app that ran constantly on her company-issued iPhone and tracked her 24/7. After voicing her objections and disabling the app, she claims she was fired from the company, according to the lawsuit, which was obtained by Ars Technica.

The lawsuit highlights how corporations are increasingly using technology to track and monitor employees, which is raising concerns about worker privacy. Given that employees often work at home in the evenings or weekends -- checking email or finishing projects -- the line between work and home life can easily become blurred.

"Employees have reasonable expectations of privacy outside the workplace, and they should feel free to assert themselves," Gail Glick, an attorney who is representing Myrna Arias, told CBS MoneyWatch. "She was fired because she was vocal about her complaints."

The boundaries between the workplace and individual privacy are "being lost for a lot of Americans, and it's devastating to those of us who believe in individual rights," Glick added. She noted that a company has "no legitimate interest in knowing where your employee is off the clock, even during lunch."

Meanwhile, tracking employees is itself an emerging business, with more than 20 companies now selling software tools for analyzing and monitoring employee behavior, according to Bloomberg News.

Intermex was allegedly tracking employees in order to monitor whether it needed to buy company cars, Glick said. According to the lawsuit, the company asked the plaintiff, Arias, and other workers to download an app from a company called Xora to their smartphones. Xora uses a GPS system that tracks workers via their phones, prompting Arias to ask Intermex if it planned to monitor employees outside of work hours.

Her boss allegedly "admitted that employees would be monitored while off duty and bragged that he knew how fast she was driving at specific moments ever since she had installed the app on her phone," the lawsuit states. "Plaintiff expressed that she had no problem with the app's GPS function during work hours, but she objected to the monitoring of her location during non-work hours."

According to the complaint, Arias told her boss it was an invasion of privacy and compared it to "a prisoner's ankle bracelet." Her boss allegedly "replied that she should tolerate the illegal intrusion because Intermex was paying" her more than her former employer, and that she was required to keep the phone on 24 hours a day, seven days a week, in order to take client calls.

The lawsuit alleges her boss "scolded" her when she took the app off her phone in April 2014 because of privacy concerns. The complaint claims she was fired from her $7,250-per-month job the following month.

Intermex didn't immediately return a request for comment. ClickSoftware Technologies, which owns Xora, declined comment.

Many software products that track employees are designed to catch hackers and corporate spies. Technology has made such behavior easier, given that an employee can email confidential information to rivals simply by pressing "send."

Some software programs used to monitor workers search their computers for sensitive words that could signal an employee is in financial distress, and more likely to present a risk, such as references to "medical bills" or "late rent," according to Bloomberg. Another company called Securonix uses algorithms to create profiles of normal behavior for each employee, such as when he or she logs in and out, which then alerts bosses when behavior deviates from the norm.

"What we're trying to do is get this situational awareness," Igor Baikalov, chief scientist at Securonix, told Bloomberg. "The next step is predictive analytics: How can we detect the small changes and stop the bad thing from happening?"

While companies may simply be trying to protect themselves from hackers and bad apples, tracking workers during off-work hours could be violating some state laws. Several states, including California and Texas, have laws that bar the use of mobile tracking devices to track other individuals, according to the National Law Review.