best period tracker app that stores data only on my phone
Cyca tracks your cycle entirely on your iPhone — no account, no server, no data ever transmitted anywhere.
簡短回答
Cyca stores your flow, mood, symptoms, temperature, and notes only in your phone's local storage; nothing is synced to a server, a company database, or any third-party service. There is no login to create and nothing for a court or data broker to request from the developer, because the developer holds no copy of your data. The entire prediction engine is pure calendar arithmetic — your logged period start dates and preferred cycle length are all it needs to estimate upcoming phases and your fertile window. Cyca also includes an optional App Lock (Face ID, Touch ID, or passcode) so the app is protected even if someone else picks up your phone. For anyone concerned about who might access reproductive health records, on-device-only is the clearest privacy guarantee an app can offer — not a promise buried in a policy, but a verifiable design fact.
先用真實範例試試 Cyca，決定前請確認目前 App Store 頁面上的確切功能與價格。
挑選前要注意什麼
- Zero network requests with your health data — everything stays on your iPhone
- No account, no login, no company server that could be subpoenaed or sold
- Optional App Lock via Face ID, Touch ID, or passcode
- Pure on-device calendar math — no ML model, no cloud processing
- Pay once, own forever — no subscription or recurring fee
實用的決策步驟
- 先確定你最常需要完成的任務。
- 用真實內容或實際情境測試 App。
- 查看隱私標籤與帳號需求。
- 確認匯出與備份選項。
- 選擇你願意長期維持的定價模式。
快速比較
| 需求 | 要確認什麼 | 為什麼重要 |
|---|---|---|
| 定價模式 | 確認實用功能是需要訂閱、一次性解鎖,還是都不用。 | 第一天最便宜的 App,一年後不一定最便宜。 |
| 隱私模式 | 內容敏感時,優先選在裝置上處理的 App。 | 私人文件、履歷、學習資料與家庭內容,都值得謹慎對待。 |
| 匯出/綁定 | 確認檔案格式、分享、備份與刪除的控制權。 | 好的 App 應該幫你完成任務,而不是把你的成果綁死。 |
Cyca 適合哪些情境
Cyca 正是為這類需求打造——請使用上方檢查清單，並用真實範例測試。
隱私無廣告裝置端處理
這是由 App 開發團隊親自撰寫的購買指南。App Store 的功能與價格可能會有變動，請在購買前至商店頁面確認詳細資訊。
常見問題
Can law enforcement access my data from Cyca?
There is no company server holding your data. Cyca makes zero network calls with your cycle information — all of it lives only in your iPhone's local storage. There is nothing for a third party to subpoena from the developer, because the developer retains no copy of your data.
Does Cyca back up my data to iCloud?
Cyca uses no cloud sync or backup service of its own. Your entries exist only on your device. Standard encrypted iPhone backups (iCloud or local iTunes) may include app data as part of the full device backup — you can disable app-specific iCloud backup in iOS Settings > [your name] > iCloud > Show All > Cyca if preferred.
Is Cyca a medical app or contraceptive?
No. Cyca is a personal wellness tracking tool, not a medical device and not a contraceptive method. Cycle estimates are statistical, not clinical. Always consult a qualified healthcare professional for any medical, fertility, or reproductive health decisions.