Literally the biggest waste of money on… Literally the biggest waste of money on the entire planet. Doesn't sync with your phone, takes forever to take your temperature and straight up doesn't work. I have reached out to customer support multiple times and they have told me to download beta versions of their app and all different types of solutions and nothing ever works. Absolutely garbage. Don't waste your money.

Definitely not worth your money This has to be my biggest Amazon purchase regret and I wish I could return it after 4 months of trying. It is so hard to use, hard to remember how to use, the app sucks, and this technology is not nearly as smart as it leads you to believe. You can’t track your period start days unless you remembered to take your temperature that morning and you can’t go back and update information from over 3 previous days so if you forgot to take it your temperature you’re screwed. You have to manually sync the Daysy to the app and the app to the Daysy- this is fairly straightforward but not something you’d expect from a €300 device. The app feels outdated and pales in comparison to competing apps like Flo. I sincerely do not know how this has 5 star reviews on every platform. If it were €20, it’s totally worth the money. Maybeeee €100. But €300 is ridiculous for how cheap it feels, how outdated it is, and how complicated it is. I seriously doubt this was even made by women for women.

Very expensive mistake to purchase. I have been beyond disappointed with the Daysy I purchased. I waited very long to get the new version (their website said the wait would be much less than it actually was which screwed up our family planning with our doctor that we started based on the websites indicated ship date). It takes at least two tries to take my temperature every morning and each try takes over two minutes. It very rarely actually syncs with the app. I've contacted support several times and they've been rude every time. I am not the only one having issues but they still make it feel like it's my fault. Definitely not worth what they charge for it! I was going to return it but decided to give it a chance. Big mistake. I also take thyroid medication which apparently screws up the readings but isn't mentioned anywhere in the information so a doubly worthless version expensive device.

Works extremely well Daysy helps me monitor my fertility for preventing pregnancy, and it has worked perfectly so far. The app is great and I have had no issues with the device or the app. I love being able to download the charts and analyze my biology. Once I got a higher number of red and yellow days, so I reached out to customer support. Within one business day someone responded and provided an in depth analysis and advice.

Careful If you are thinking in investing in this device you need to remember one important thing: Daysy is, in the end, just a fertility tracking method. It DOESN'T protect you from unwanted pregnancy (even though the company tries to sell it as if it would, in a very subtle way, and of course without taking any accountability). I got unwanted pregnant with it 2 times, now we switched on using condoms only religiously. I know from 2 other women in my friends circle who had the same "accident". So, please be careful. I still keep the device tho, in the case i will want a baby in the future, because it gives you a better overview of the best fertile days. Oh, one more thing: Beware of the paid reviews (that are in high amount on Trustpilot as well) ;)