---
title: BBT and ovulation tracker for iPhone: basal temperature and LH tests
description: Track basal body temperature and LH ovulation tests on iPhone: a BBT chart with a coverline, positive LH tests that move the period forecast, and two-way Apple Health sync. Free.
url: https://www.arbazsiddiqui.me/app/iris/bbt-ovulation-tracker/
---

# A BBT and ovulation tracker

Log your morning temperature and LH test strips. Iris charts temperatures against a coverline and uses a positive LH test to mark ovulation and reset the countdown to your next period.

App Store: https://apps.apple.com/app/id6761134901

## Basal body temperature

After ovulation, progesterone raises your resting temperature a little: Cleveland Clinic gives the rise as anywhere from 0.4 °F (0.22 °C) to 1 °F (0.56 °C) ([Cleveland Clinic: basal body temperature](https://my.clevelandclinic.org/health/articles/21065-basal-body-temperature)). It is small, so take it as soon as you wake, at about the same time each morning. Iris charts each reading against a coverline so the rise after ovulation is easy to see.

## LH tests

LH tests pick up the hormone surge that comes before ovulation. Log a positive test and Iris marks ovulation on the calendar and moves your period prediction to match, so a late ovulation shifts the forecast instead of making the period look late.

## Works with Apple Health

Basal temperature and ovulation tests sync both ways with Apple Health, so readings from a connected thermometer or another app land in Iris without typing them twice.

## Trying to conceive, or not

Pick a goal mode: trying to conceive, avoiding pregnancy, or just tracking. Colours and wording change to fit. Temperature alone is not reliable birth control ([Cleveland Clinic: basal body temperature](https://my.clevelandclinic.org/health/articles/21065-basal-body-temperature)), and Iris never marks a day as safe.

## Questions

**Does Iris draw a coverline?** Yes. Temperatures are charted against a coverline so the post-ovulation rise stands out.

**Can I log LH test strips?** Yes. A positive LH test marks ovulation on your calendar and resets the countdown to your next period.

**Can I use temperature tracking as birth control?** No. Iris is not a contraceptive and its predictions are estimates.

Iris is not a contraceptive. Its predictions are estimates.