Life expectancy calculator app for iPhone: five checks before you trust one

Check 1. Does it name its baseline table?

Every credible estimate starts from a published mortality table, not from the questionnaire. A period life table gives, for each single year of age and each sex, the average number of further years a person can expect. The United States Social Security Administration publishes one, the United Nations publishes country level figures, and the World Health Organization publishes another.

If an app never names the table it starts from, it is not adjusting a baseline. It is scoring a quiz and calling the score a year.

Yorick: the SSA period life table for 2022, bundled inside the app, read at your exact age and interpolated between whole years.

Check 2. Can you open the study behind any single factor?

This is the strictest test, and almost nothing passes it. It is easy to write that a source is peer reviewed research. It is much harder to attach a specific paper to a specific number and let the user tap through to it, because then a reader can check whether the effect size in the app matches the effect size in the paper.

Ask the harder version of the question: not does it cite research, but can I see which paper produced the seven years it just took off my life?

Yorick: every factor carries a named study with a link to PubMed, opened from the factor itself. The full list is published on the 19 questions page as well, so you can read the scoring sheet before you install anything.

Check 3. Does it show you a margin?

A single date with no range is a presentation decision dressed as a result. The underlying table describes a population with an enormous spread: among people who share your age and sex, some die next year and some reach a hundred.

An app that hides that spread is not more accurate than one that shows it. It is just less honest about being an estimate.

Yorick: every result carries a likely range. It is never narrower than three years, it widens with the amount of life left, and nothing is projected past age 105.

Check 4. What does it actually cost, and is it a subscription?

This category has drifted toward recurring pricing, and some of the better known apps in it are annual subscriptions in the region of one hundred dollars a year. Sometimes that buys real ongoing service, such as blood panels or coaching. Sometimes it buys a number that does not change until you change your answers.

The question worth asking is whether what you are paying for is genuinely recurring. A life expectancy estimate from a questionnaire is not.

Yorick: free to download, and the full result is free. Yorick Pro is one non-consumable purchase of $4.99 that unlocks the what-if levers, the Lab, the factor breakdown, the country comparison, and removes the ads. It is tied to your Apple ID and restores on a new iPhone. There is no subscription.

Check 5. Where does the calculation run?

Your answers to a lifespan questionnaire are among the most sensitive things you will type into a phone: smoking, drinking, weight, diagnoses, depression, isolation. It is worth knowing whether they travel.

Two separate questions hide inside this one, and apps often answer only the flattering one. First, does the health calculation itself need a server? Second, does the app contain any other component, such as an advertising library, that talks to the network for its own reasons?

Yorick: the mortality tables and every effect size ship inside the app, so the estimate is computed on your iPhone and your answers are stored in the app's own folder on the device. There is no account and no sign up, and deleting the app deletes them. The free version is supported by ads served through Google AdMob, which asks for your advertising consent choices when you first open the app; Yorick Pro removes the ads. Both facts are worth stating plainly rather than one of them.

iPhone, iOS 26.0 or later, about 5.8 MB.