Yes, because trackle is approved as a class IIb medical device as a contraceptive. trackle supports you in determining your personal cycle status and can be used to determine the fertile and infertile days

If you do not want to get pregnant, you must not introduce pre-ejaculate or sperm into the vagina on the days determined as fertile. You must use a contraceptive method of your choice (e.g. condom) during the fertile period. The reliability of contraception during the time that trackle has recognised as being “fertile” depends on the contraceptive you use. The safest choice is to refrain from vaginal intercourse during the fertile days. 

trackle does not provide 100% certainty in determining the infertile days. As with all methods of contraception, there is a residual risk of getting pregnant during unprotected intercourse. In other words, with trackle you know when you can get pregnant and when you cannot. And you also know when you need additional contraception and when you don't. 

Find out more about hormone-free contraception here.