It's just a way for stupid people to part with more of their money.
As already stated, if one already suspects their spouse of cheating, enough to do something about it..
Then they're likely cheating. And breakup ensuse because innocent spouse gets pissed off enough.
If there is a spouse who's cheating, then generally, they're sloppy. That is, they in some twisted way, *want* to get caught.
If one is just plain paranoid their spouse is cheating, but they're not... (rare, but does happen)
Then they're not cheating. And breakup ensuse because innocent spouse gets pissed off enough.
If it's just paranoia in play, then said paranoid isn't quite ready for a relationship, they need to sort out their own shit before contining.
Either way, this has been happening since time immemorial. People have been dealing with it for a whopping long time before smartphones, and as I've said, they tend to leave enough clues that you don't need to tap phones anyway.
Having assisted others on this matter, it's never legal, it's never admissable in court, and serves only to confirm what they already knew.
So why spend money on it?