Eye Charts

Fonlow

About this app

Eye Charts is a professionally designed visual acuity testing app that makes it easy to accurately check, record, and track vision over time in children aged 6 and above, whether you are a parent monitoring a child’s eyesight at home or a healthcare professional performing routine screening in practice. Early detection of myopia allows you to take preventive action, seek medical advice promptly, and prevent pseudomyopia from worsening into myopia or stop nearsightedness from deteriorating further.

DESIGNED TO REDUCE VARIABILITY
Unlike paper charts that fade, warp, or become memorized over time, Eye Charts presents optically accurate optotypes that are randomized for every test. This helps ensure more meaningful results for repeated testing at home, in schools, clinics, or telehealth settings.

Supported charts include:
* Snellen
* ETDRS
* Landolt C
* Tumbling E
* HOTV
* Numbers
* Shapes

The charts use LogMAR scaling of letter size across rows, and support multiple visual acuity notations for scoring, including: Fraction, LogMAR, MAR, Decimal and VAS.

Flexible test distances allow accurate use in small rooms, hallways, or ad‑hoc spaces.

Displayed on iOS and Android devices, Eye Charts is self‑illuminated, so the chart’s visibility does not depend on room lighting or weather. Screen brightness is adjustable and can be set appropriately for longer testing distances such as 6 meters.

Scenarios:
1. Doctor and Patient.
2. Self-diagnosis using a mirror – Stand in front of a mirror with the app in mirror mode, wearing an eye patch over one eye. The effective test distance is twice the distance between you and the mirror.
3. Self-diagnosis using a Bluetooth keyboard – Place the device a few meters away on a table, and use the keyboard arrow keys to indicate what you can read.

SEE TRENDS, NOT JUST SNAPSHOTS
Test results can be recorded for individual subjects and visualized over time using simple line graphs, making it easier to identify:
* Gradual changes in vision
* Stability after intervention

This longitudinal view is valuable for parents monitoring children’s eyesight and for clinicians tracking changes across visits.

INDEPENDENTLY EVALUATED ACCURACY
Eye Charts was previously published as Visual Acuity Charts. Under that name, it was independently evaluated in a peer‑reviewed academic study published in JAMA Ophthalmology and available via PubMed Central on https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7809609/. In that study, researchers objectively compared multiple iPhone‑based visual acuity apps by physically measuring optotype accuracy across devices. Visual Acuity Charts demonstrated the lowest measurement error among the apps evaluated, making it the most accurate app tested in that comparison.

Myopia detection involves several steps, with distance visual acuity testing often being the first. A decline in visual acuity may indicate the onset of myopia, enabling early intervention.

DISCLAIMER:
While this app may replace printed eye charts, it CANNOT replace doctors or optometrists who perform comprehensive eye exams essential for maintaining eye health. The app does not test for strabismus, esotropia, exotropia, hyperopia, or astigmatism—common early vision conditions. Please consult an optometrist regularly and seek professional medical advice at the first signs of visual acuity issues.

Ratings and reviews

Fairly accurate as I had measured the size of optotypes with a ruler. And the brightness of the app could be independent of my phone's brightness setting since I generally keep low brightness, while testing from a distantce requires brighter background.

Handy to use to check up visual every now and then

works on my S23 Ultra (worst phone I've ever owned).

What’s new

1. Support 16KB Memory Page Sizes.
2. arm64-v8a only.
3. Adjust the privacy policy to clearly state the data usage.