I don't know of any right off hand that I'd trust. A lot of those you find when searching the web are in fact bogus and often expensive scams. Also, if the target phone is anything less than a full-fledged smartphone (i.e. iPhone, Android device, Blackberry, Windows Phone, or at least an old Symbian or PalmOS smartphone), the average feature phone wouldn't be capable of running complex background processes and applications such as a monitoring/tracking app, anyway.
Now, aside from the technical issues...
It seems like an awful lot of trouble to go in order to spy on someone - I'm assuming the target is a spouse or significant other, but I suppose it could as easily be a minor child or dependent. In either case, the solution(s) may be far simpler (at least in concept), but far more difficult for some people to accept:
If it is in fact an adult you wish to spy upon, doesn't it make more sense that you take a hard look at why such mistrust exists to begin with? Perhaps a history of dishonesty and betrayal? Typically, that kind of suspicion and subsequent insecurity spell eventual disaster for a relationship. Even if your amateur sleuthing efforts were to yield no proof of wrong doing, a suspicious mind is likely to come up with a dozen ways for their supposedly sneaky loved one to have circumvented their spying efforts,(and that may even be a correct assumption; there are ways around any technical monitoring measures you could hope to emply). In which case, you'd have wasted your time with this placebo effort at placating yourself, and further dodged the truth:
Better to accept that either A) the person you wish to monitor is already unworthy of your trust, that you're just looking for excuses to forestall the inevitable, and that you should part ways immediately, or B) you have trust issues that you need to work on -alone- before being capable of healthy relationships, and that you should STILL part ways with this person, so you can address those issues before entering into relations for which you are simply not equipped.
And if the subject of your proposed spying effort is a dependent child, then you clearly need to play a more direct and active role in their lives, rather than depending on some technical means to substitute or compensate for your inattention and/or your child's lack of instilled discipline.