Ask us anything.
If you can’t find your answer here, send us a message below.
Buying Cycle0
Why can’t I try it before buying?
To offer a free trial, an app has to identify who you are so it can cut off access when the trial ends—which means tracking users, requiring accounts, and checking in with a server. Those are the exact practices we refuse to build.
Instead, we charge $4.99 once, everything included, and you can see every real screen on this site before spending anything. If it turns out not to be for you, standard App Store and Google Play refund policies have you covered.
What do I get for $4.99?
Everything. Daily tracking, calendar views, trends, all five optional advanced logging tools, printable PDF and CSV reports, encrypted backups, app lock, six light and dark themes, all 14 languages, and both phone and tablet layouts. There are no subscriptions, no locked features, and no extra costs for updates.
Do I have to pay again for my other devices?
Not within the same app store account. A single purchase covers your phone and tablet, and Apple and Google family sharing work wherever supported. If you switch between Apple and Android, they are separate stores and we cannot link purchases across platforms—doing so would require tracking your identity, which we refuse to do.
Can I get a refund?
Yes, directly through the App Store or Google Play under their standard refund terms. We never handle your payment details ourselves, so Apple and Google manage all refunds on our behalf.
Privacy & Security
Do you really have no servers for the app?
None that your entries can reach. Cycle0 has no accounts, no cloud sync, no analytics, and no crash reporting. Put your phone in airplane mode and the app works identically—that’s the easiest way to verify it yourself.
What about this website and the contact form?
This website runs on a secure, Switzerland-based server. Visiting it sets just one cookie—remembering your language preference—and runs zero tracking scripts. If you use the feedback form below, your message passes through our Swiss hosting provider to reach our inbox. Any server logs generated while sending are governed by Swiss privacy law and used strictly to keep the form working safely.
What happens if I lose my phone?
Because your entries live solely on your device, we cannot recover them if your phone is lost without a backup. You can easily enable automatic, encrypted backups to your own iCloud Drive, Google Drive, or a local file directly within the app’s settings.
Can someone who picks up my phone read my entries?
Not if you turn on App Lock. You can secure Cycle0 with a PIN, Face ID, or fingerprint so the app locks immediately whenever you put your phone down.
Using the App
Does it predict my period? Can I use it as contraception?
Cycle0 can show an expected next period date once your recent history is consistent enough, and it is always labeled as expected or likely—never certain. No app can guarantee when a period begins. Cycle0 is an informational tracker only: it is not contraception, not a fertility method, and not a medical diagnosis, and it should never be relied on to avoid or plan a pregnancy.
My cycles are irregular. Is Cycle0 for me?
Yes. When your cycles vary too much for an honest estimate, Cycle0 removes the predicted date rather than giving a bad guess. Instead, it presents clear facts: days since your last period, your shortest and longest recent cycles, and your full history. If your cycles settle later, the estimate returns automatically.
What if my periods have stopped?
You can update this in Settings with a single tap, and the app will quietly switch to counting months instead of cycles. Nothing you’ve logged is lost. Any bleeding logged after that point is shown with a calm, neutral display—no alarming colors, warnings, or pop-ups.
What are the optional advanced tools?
Five extra tools, off by default, for when you want deeper records: pain, bowel, bladder, daily impact, and medications.
Turning one on adds a discreet card to your daily entry. The pain tool uses clear, descriptive language (such as "stopped me working") and a simple body map, helping you show a doctor exactly where and how it hurt. Side-by-side comparison
Can I customize my symptoms list?
Yes. You can hide symptoms you don't experience, reorder the list so your frequent ones sit at the top, and add custom symptoms in your own words.
Which languages and devices are supported?
Cycle0 supports 14 languages: English, Español, Français, Deutsch, Nederlands, Italiano, Português, Русский, Polski, Svenska, Türkçe, 한국어, 日本語, and 中文.
It runs on iPhone, iPad, Android phones, and Android tablets. Everything works entirely offline, as it always should.
How do you fix bugs if you don’t collect app data?
You tell us. If something isn't working right, describe what happened using the contact form below—including your device model and OS version helps a lot. Please do not send your personal diary entries or exported files; we don't need them to fix bugs.
Still have something to share?
Send it directly to us. No accounts, no tracking—just your message.
Send anonymously: Leave the name and email fields blank. We will read your message, but won’t be able to reply. Want a reply? Include your name and email. We’ll only use your address to reply—never for marketing lists.