For Warfarin · Sintrom · Coumadin

Take control of your blood‑thinner therapy.

INRythm is a simple, private tracker for your daily dose and INR results. Built by a heart-surgery patient — for everyone living with long-term anticoagulants.

Private by design. Encrypted in transit, never sold to third parties.
Built for people who can't afford to forget a dose

Three things, done well.

No bloat, no social feed, no ads. Track your dose. Track your INR. Get reminded. That's it.

Daily dose tracking

Log every dose with a single tap. Confirm with the time you actually took it. Never wonder "did I take it today?" again.

INR results, visualised

Plot your INR over time and see at a glance whether you're inside your therapeutic range. Spot a trend before it becomes a problem.

Smart reminders

Notifications for your daily dose at the time that suits you, plus reminders for upcoming bloodwork checks.

A look inside

Designed to be glanceable.

Open the app, see your day, log your dose. The whole interaction is meant to take ten seconds.

INRythm dashboard in dark mode showing today's 3mg Sintrom dose, a 14-day dose history chart, and the latest INR reading

Dashboard. Today's prescribed dose, your 14-day history, and your latest INR reading — at a glance.

INRythm dashboard in light mode with the same data, showing the app respects your system theme

Light mode too. Every screen respects your system theme. The data, the typography, the rhythm — all the same.

INRythm therapy log calendar showing every day's dose and INR test markers across the month

Therapy log. Every dose, every test, every missed day — the full month at a glance.

INRythm therapy log with a day selected, showing the dose taken and the INR test result for that day

Tap any day. See exactly what you took, when, and the INR result — even months later.

INRythm settings showing INR target range, check frequency, theme, date format, and CSV export options

Settings. Set your target INR range, reminder time, and check frequency once. Then forget about it.

Built by a patient

One of us made it.

Ivan Georgiev, founder of INRythm
I created INRythm after my heart surgery. The doctors saved my life with an artificial heart valve, and now I take Sintrom for life. If you're reading this, there's a good chance you're on it too. INRythm is the simple, reliable tool I wished existed.
FounderIvan Georgiev

Works with every major anticoagulant

If your medication is a vitamin K antagonist, INRythm tracks it.

SintromAcenocoumarol
WarfarinGeneric
CoumadinWarfarin
MarevanWarfarin
MarcoumarPhenprocoumon
JantovenWarfarin
FalithromPhenprocoumon
Other VKAsVitamin K antagonists
Frequently asked

Common questions.

If we missed yours, write to us at inrythm@shtrak.bg.

What is INR and why do I need to track it?
INR (International Normalized Ratio) measures how long your blood takes to clot. If you take a vitamin K antagonist like Warfarin or Sintrom, your doctor sets a target range — typically 2.0 to 3.5, depending on your condition. Staying inside that range matters: too low and you risk a clot, too high and you risk bleeding. Tracking your INR over time helps you and your doctor adjust your dose with a clear record, not guesswork.
Which medications does INRythm support?
Every major vitamin K antagonist: Sintrom (acenocoumarol), Warfarin (Coumadin, Marevan, Jantoven), Marcoumar and Falithrom (phenprocoumon), and others. You set your medication name and target range once during setup.
Does INRythm replace my doctor or anticoagulation clinic?
No. INRythm is a personal tracking tool, not medical advice. Always follow your doctor's prescribed dose and your clinic's testing schedule. INRythm makes the record-keeping easier, so the conversations with your care team are clearer.
Where is my data stored? Is it private?
You sign in with email and password, and your dose log, INR readings, reminders, and settings are stored in Google Firebase on Google Cloud, encrypted in transit. Each account is fully private — we don't share your data with anyone, and we never sell it. You can delete your account from inside the app at any time, which wipes your synced data. The App Store privacy disclosure reflects this: any health data we collect is "Not Linked to You."
Does INRythm work without internet?
Mostly. You'll need a connection to sign in and to sync your latest log across devices. Once signed in, the app works offline for logging doses and viewing your history — it'll sync the next time you're online.
Can I export my data to share with my doctor?
Yes. From Settings → Data, export your dose and INR history as a CSV file you can email, print, or hand to your anticoagulation clinic.
Is there an Android version?
Yes. INRythm is available on both iOS and Android. Download from the App Store or get it on Google Play.
How much does INRythm cost?
INRythm is a paid app. We don't show pricing on this site because it varies by country and currency — you'll see your local price on the App Store or Google Play before you commit. There are no in-app upsells, no ads, and no subscriptions hidden behind features.
What happens if I miss a dose?
Mark it as missed in the app. INRythm will show that day with a missed-dose marker so the gap is visible to you and your doctor. Always follow your doctor's guidance on what to do next; never double up unless they tell you to.
How do I change my target INR range?
Settings → Monitoring → Target range. Update it whenever your doctor adjusts your therapy. The change applies going forward — your historical data stays as it was.
How do I contact support?
Email inrythm@shtrak.bg. A real person reads every message.

Start tracking in 60 seconds.

Set up your medication, your target range, and your reminder time. Then close the settings and forget about them.

PAID APP · NO ADS · ENCRYPTED IN TRANSIT