I use Natural Cycles - an app that determines your fertile and not fertile days based on the temperature shift. I've been using it for a few months now, before I only used a period tracker and wasn't happy enough with it so I looked into getting something smarter. I took hormonal contraception for a about two years and it messed my body so much I promote the natural approach everywhere I can. I got endometriosis and the hormones I took (the pill, implant, injections) let it grow further undercover. It was supposed to ease the symptoms and periods, but all it did is made me unhappy, depressed, and in fact increase the endometriosis symptoms to the level that I couldn't bare it any longer and had to have a surgery. I refused to take any hormones after even though my doctors insisted on them 'being helpful'.
Since I've started using Natural Cycles, I learnt a lot about my cycle and my body as a whole and it helps me to plan my life around my cycle. I read a lot about it and I learnt how to use it correctly and now I'm not afraid of unwanted pregnancy and feel confident that when I decide on having a baby I won't have any problems restoring my fertility as it's not suppressed by artificial hormones and will be able to determine the best times for trying. Can't recommend enough. I've been artificial contraception free for two years now.
After reaching the #ProCycler status - adding temperature more than 70% of the time and using the app for a few months I was given this referral code with a 30% off a year subscription and a free thermometer for any one who wants to join!