Answers to what people actually ask. If none of this helps, write to gelistirbizi@gmail.com and you will get a reply from a person.

The app says it cannot get a reading

Almost always light. The pulse is a fraction of a percent of the brightness of your skin, so the app needs enough light, and more importantly, even light. Face a window or a lamp rather than sitting with one behind you, avoid harsh direct sun, and keep your head still: talking, smiling and nodding all move the skin more than the heartbeat does. Fill the oval with your face, at about arm's length.

It gave me a pulse but said the variability was low signal

That is the app being honest rather than failing. A pulse rate is an average over fifteen seconds and survives a lot of noise. Variability is the difference between one beat and the next, so the same noise affects it far more. When the recording is not clean enough, the app shows the figures but marks them, and keeps them out of your baseline and trends. Better light and a stiller head usually fix it.

The number is different from my watch or chest strap

Expect pulse to agree closely and variability to agree less closely. A chest strap measures the heart's electrical signal directly; this measures light reflected off skin. They are different measurements of related things. Variability also changes genuinely from minute to minute, so two devices measuring at different moments will disagree for real reasons as well.

What is a good RMSSD?

There is no useful answer to that, which is why the app does not give one. Healthy adults span an order of magnitude, and the figure falls with age and rises with fitness. What is useful is your own trend: measure at the same time each day, and after five readings the app starts scoring each one against your own average instead of a stranger's.

I bought Pro but the features are still locked

Open Settings and tap Restore purchases. That asks the store who you are and re-applies anything you own. It is also what to use on a new phone, as long as you are signed in with the same Apple or Google account you bought with.

How do I cancel a subscription?

On iPhone: Settings, tap your name, Subscriptions. On Android: Play Store, your profile picture, Payments and subscriptions. Deleting the app does not cancel anything. The lifetime option is a single payment and has nothing to cancel.

I lost my readings

They are stored on the device and nowhere else, so if the app was uninstalled or the device was reset they are gone and cannot be recovered, by you or by us. That is the direct cost of having no account and no server. Export to CSV from the Trends tab if you want a copy you keep.

Does it work without internet?

Entirely. Measuring, the report, trends and export all work in airplane mode. A network is needed only to complete or restore a purchase.

Which languages does it speak?

English, German, Spanish, French and Turkish. It follows your phone's language by default, and Settings can override that.

Contact

Safiye Meram, Esenler/Istanbul, Türkiye
gelistirbizi@gmail.com
Replies within a few working days.