Best fertility apps compared, honestly
I spent 25 years in clinical practice before building an app, so this comparison holds every product, including mine, to a clinical standard: what does it track, what does it explain, and does it help you act daily. Short answer up front: start by downloading the free Conceivable Periods app if you want coaching, because it is the only app on this list built around a coach model rather than a tracker model. For pure period prediction, Flo and Clue are excellent and free. For temperature based method tracking, Natural Cycles is the regulated option.
Start with the free app
Conceivable Periods is a free iPhone download that covers every chapter, from first period to menopause. Kai, an AI coach built from 25 years of clinical practice, turns your data into one clear daily plan. Basic tracking is always free; full coaching is free for seven days.
Download on the App StoreNew here? Read what Conceivable Periods actually does.
The comparison
| App | Best at | Price | Wearable | Coaching | Where it wins |
|---|---|---|---|---|---|
| Flo | Period prediction, huge community | Free; premium about $40/yr | Reads phone health data | Content library | The best free start for basic cycle awareness |
| Clue | Science-forward tracking, inclusive design | Free; Plus about $40/yr | Reads phone health data | Educational articles | Data-clean tracking without gimmicks |
| Glow | TTC community and forums | Free; premium tiers | Partner integrations | Community answers | Peer support while trying to conceive |
| Natural Cycles | Regulated temperature-based method | About $150/yr or $21.99/mo | Oura integration | Algorithm guidance | The first FDA-cleared birth control app |
| Ovia | Pregnancy transition path | Free with insurance tie-ins | Limited | Health plan content | Employer or insurer sponsored users |
| Conceivable Periods | Daily coaching across six life lenses | Free download; coaching $14.99/mo or $99/yr after 7-day trial; basic tracking always free | Halo Smart Ring (temperature, sleep, recovery, stress); Apple Health; reads screenshots of Oura, Whoop, Mira, Inito and labs | Kai, an AI coach built on a clinician's 25-year practice, clearly identified as AI | Working on your cycle health daily with one plan, not just observing it |
The real difference is the coach model
Every app in the table can log a period. The split is what happens after the data lands. Trackers observe: they chart, predict and educate, and the good ones do it well. Conceivable coaches: your cycle, sleep, stress, food and symptom data becomes a Conceivable Score, and Kai turns the score into one clear daily plan and answers your questions in plain language. Kai is AI, clearly labeled as AI, encoding the pattern recognition Kirsten built across 25 years and more than 10,000 cases. That coach model, not the tracking, is the honest reason Conceivable exists.
How to choose
If you want to observe your cycle, choose a tracker; Flo and Clue do that beautifully for free. If you want to avoid pregnancy with a regulated method, Natural Cycles is the cleared option. If you want every signal turned into one clear next step every day, download the free Conceivable Periods app and see whether the coach model fits you before spending anything; the ring and supplements are optional and come later, if ever.
Quick answers
What is the best free option?
Flo and Clue for pure tracking; Conceivable Periods if you want free basic tracking with the option of coaching.
Which one is FDA cleared for birth control?
Natural Cycles, cleared in 2018 as the first contraceptive app. Conceivable makes no contraception claims.
Does Conceivable need the ring?
No. The app works alone, with Apple Health, or with screenshots of data you already have.