It's bad enough checking your partner's phone when they leave the room, or taking a peek at their Facebook page, yet a new app takes this level of snooping not just a step further, but a giant leap forward.
The mSpy app works on select smartphones including Apple, Android, BlackBerry and Windows Phone and can be used to gain access to an unprecedented level of personal information.
It records phone calls, tracks a person's location, lets users remotely read texts, Skype, Facebook and Viber messages, view browsing history and even see how much battery the phone has left.
According to Oregon-based mSpy's website, the app is designed for "monitoring your children, employees or others on a smartphone or mobile device."
However, it adds the person doing the spying must own the device being tracked, or the person being tracked must give his or her permission.
Spies can also use the app to view videos and photos stored on a device, see the phone owner's list of applications and software updates, open their calendar, notes and tasks, and even get hold of the phone's unique IMEI number.
They can additionally remotely lock or wipe a device, block websites and calls from certain contacts as well as record the person's surroundings.
People wanting to use the app do need to physically install it onto the phone they wish to track, yet once installed mSpy promises the app is 100 percent undetectable.