Your fertility tracker, back in your hands.

Rise is a calm, private app for tracking your cycle. It gives a second life to the Ovy OT35 thermometer on phones the official app no longer supports - and it works just as well on its own, without any device.

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Free and open source. No account. No cloud.

Why Rise exists

Maybe you have an Ovy OT35 - a small Bluetooth thermometer that measures your temperature each morning and sends it to your phone. It is a lovely little device, and it still works perfectly.

Then one day the official app stopped opening. Not because anything broke, but because a newer version now asks for a more recent Android phone than yours. The thermometer is fine. Your phone is fine. But the app that connects them has moved on and left you behind.

That is how a working device quietly turns into a drawer full of e-waste - not because it failed, but because the software stopped talking to it. We did not think that was fair, so we built Rise: an app that speaks to the OT35 directly and puts your measurements back where they belong, with you.

No thermometer? Rise still works.

You do not need the Ovy device - or any device - to use Rise. You can type your morning temperature and the other daily signs in by hand, just like a paper chart, and the app does the rest. The thermometer simply saves you the typing.

What it does

Everything a symptothermal chart needs, in one quiet place.

📈

Reads your temperature

Connects to the Ovy OT35 over Bluetooth and pulls in your morning readings automatically - or lets you enter them by hand.

🌙

Charts your whole cycle

Temperature sits alongside the other daily signs so you can see the full picture at a glance.

✅

Marks your fertile window

Follows the well-established Sensiplan method to open and confirm the fertile window from your own readings.

🔒

Keeps your data yours

Everything lives on your phone and works fully offline. No account to make, nothing sent to a company's servers.

A look inside

A calm, private view of your whole cycle.

Rise chart showing the basal temperature rise, the coverline, and the highlighted fertile window
Your cycle, charted
A single day's detail sheet with temperature, cervical mucus, cervix, mood and more
Every sign in one tap
Settings screen showing the paired Ovy OT35 thermometer, sync, and CSV export or import
Your Ovy device, synced

Join in

Rise is built by people who did not want to throw a good device away. There is a place for you here - whether or not you write code.

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Test it on your phone

Try Rise with your thermometer and older phone, and tell us what worked and what did not. Real devices in real hands are what make it solid.

🌍

Translate & refine

Help Rise speak more languages, or smooth out wording so it stays clear and kind. No programming needed.

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Share ideas & report bugs

Open an issue with a rough edge, a wish, or a quirk of your device. Every report makes the next release better.

💻

Write code

Rise is a Flutter app under the GPL. Pick up an issue, improve the Bluetooth sync, or add a feature you have always wanted.

Visit the project on GitHub Browse open issues

Get Rise

Download the latest signed APK from GitHub and install it on your phone.

Download from GitHub

Free forever, and open source.