Comparison

King vs NIH Toolbox

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

King

This application assists individuals with eye movement deficits stemming from neurological impairment. It facilitates practice with an oculomotor program, presenting number targets for reading aloud to improve vision-related symptoms after brain injury. The program offers adjustable speed settings and tracks progress.

Highlights
  • Oculomotor program practice
  • Dynamic number target presentation
  • Adjustable speed settings
  • Instant outcome measures
  • Compliance monitoring
  • Requires existing account
Features
Read full description

King-Devick Recovery Practice is the companion iPad App for the K-D Recovery Acceleration Program (K-D RAP) and helps individuals with eye movement deficits as a result of neurological impairment. Why K-D Recovery Acceleration Program? Following a brain injury, up to 90% of individuals experience vision-related symptoms. K-D RAP is a web and app-based oculomotor program. The individual reads aloud dynamically presented number targets quickly on a computer or iPad. Speed settings are easily adjusted and increased with ongoing practice. K-D RAP provides instant outcome measures and compliance monitoring over the course of recovery. About this App This app can only be used with an existing King-Devick Recovery Acceleration Program account and requires internet access to function. King-Devick Recovery Practice is intended for practicing individuals. It has been validated on iPads with a 9.7" display or larger.

About

NIH Toolbox

This legacy app provides a comprehensive set of measures for cognitive, emotional, motor, and sensory function in individuals aged 3-85. Designed for research and clinical use, it offers streamlined workflows for over 50 tests. Note: this version will be retired in June 2028.

Highlights
  • Cognitive, emotional, motor, sensory function assessment
  • Ages 3-85
  • Research and clinical use
  • Streamlined workflows
  • Over 50 tests
  • Crosswalk among measures
Read full description

PLEASE BE ADVISED THAT THIS IS A LEGACY VERSION OF THE NIH TOOLBOX SYSTEM AND WILL BE RETIRED IN JUNE 2028. New users are strongly encouraged to download the NIH Toolbox V3 app instead of this legacy version: https://apps.apple.com/us/app/nih-toolbox-v3/id1627119550. Users whose studies end after June 2028 must plan to transition to the NIH Toolbox V3 app before then. The annual subscription cost of this app will increase each year through its retirement. *** Important Hardware Note: iPads (2018 and newer models) with 9.7- to 11-inch screens are recommended. Data collected on iPads with 12.9" screens has not yet been validated. *** NIH Toolbox® is a multidimensional set of performance and person-report measures that assess cognitive, emotional, motor, and sensory function in people ages 3-85, designed for research and clinical use. The original NIH Toolbox was developed by more than 250 scientists over 6 years, and sponsored by the 15 institutes of the National Institutes for Health that make up the NIH Neuroscience Blueprint. This update to the NIH Toolbox includes streamlined workflows and user interface for 50+ tests, for stand-alone use or as part of a complete assessment battery. With the NIH Toolbox app, researchers can assess function using a common metric and can “crosswalk” among measures, essential to the process of pooling data and often necessary when a large and diverse sample is needed. NIH Toolbox does not require a subscription for many features; however, a subscription is required to record assessment responses and to view and export results. Subscriptions are offered for purchase within the app for use on up to 10 iPads. Purchased subscriptions will automatically renew unless auto-renew is turned off at least 24 hours before the end of the current subscription period. Cancellation of the current (paid) subscription is subject to Apple’s discretion. Users can enjoy a free trial period to explore the NIH Toolbox app, but data will not be saved and results will not be generated during the free trial. The free trial period will be forfeited when the user purchases a subscription. Manage your subscription by going to your Apple Account Settings after purchase. All content needed to administer NIH Toolbox tests is available in the app, though some tests require additional hardware or materials. Please create a free account at www.NIHToolbox.org to access the Administration and Technical Manuals, supplemental materials, and list of publications. With the purchase of this app, you will immediately have access to tests in the Emotion, Motor, and Sensation domains. Tests in the Cognition domain require the successful completion of a separate approval on www.NIHToolbox.org. This approval process is included in the cost of the subscription; no additional purchase is necessary. Generally, approval will be granted to researchers and clinicians with the knowledge and training to use neuropsychological tests. Contact help@nihtoolbox.org for more details. Important information about the intended use and data security: * NIH Toolbox is not intended for use outside of research or clinical application. * Users control how data is managed. Data export via iCloud, email, and File Sharing can be enabled/disabled in the app. * If iCloud is enabled on your device, you may choose to upload data exports to a folder in iCloud Drive upon generation. Please refer to Apple for iCloud security and privacy details. * Data exports (.csv format) and assessment reports (.PDF format) may be emailed from NIH Toolbox. Secured email systems must be used to protect privacy. Help us make this product the best it can be. If you have suggestions for changes, please share them with us: help@nihtoolbox.org. To learn more about NIH Toolbox, visit www.NIHToolbox.org. NIH Toolbox Privacy Policy and Terms & Conditions: https://nihtoolbox.org/privacy-policy/ https://nihtoolbox.org/terms-of-use/

Verdict

The call

The clearest difference is rating: King at 5.0 against NIH Toolbox's 1.0. King also leads on in-app purchases (none vs 5) and iOS requirement (11.0 vs 18.0). NIH Toolbox's advantage is update cadence (every 4 months vs every 19 months). On price, ratings volume, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. NIH Toolbox sells 5 in-app purchases, starting at $0.99 per 7 days. King asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

King holds the better App Store score, 5.0 against 1.0. Both are backed by a comparable volume of ratings — 2 and 1 respectively.

UpkeepUpdate frequency

King ships an update every 19 months, NIH Toolbox every 4 months. Both last shipped on October 7, 2026.

Scorecard5 real differences · 5 level
King versus NIH Toolbox: the parameters behind the verdict, then further details
ParameterKingNIH Toolbox
PriceFreeFree
Rating5.0 (2 ratings) — better1.0 (1 ratings)
Positive reviews—100.0% of reviews
Number of ratings2 — better1
Update frequencyEvery 19 monthsEvery 4 months — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPadiPad
Requires iOS11.0 — better18.0
Further details — not scored
Size178 MB715 MB
Age rating4+4+
DeveloperKing-Devick Test, LLCGlinberg & Associates, Inc

Customer experience

King

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

NIH Toolbox

All ratings1 ratings
Positive0.0%
Neutral0.0%
Negative100.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

King

No in-app purchases

5 purchases

NIH Toolbox

Subscriptions5
  • NIH Toolbox Assessments7 Days trial$0.997 Days
  • NIH Toolbox Assessments2 Months trial$499.991 Year
  • NIH Toolbox Assessments$499.991 Year
Show 2 more
  • NIH Toolbox Assessments1 Year trial$499.991 Year
  • NIH Toolbox Assessments$1299.991 Year

Questions

Is King free?
King is free to download, with no in-app purchases.
Is NIH Toolbox free?
NIH Toolbox is free to download, with in-app purchases available.
Which has better reviews, King or NIH Toolbox?
King is rated higher. King averages 5.0 out of 5 from 2 ratings, while NIH Toolbox averages 1.0 from 1 ratings.
Do King or NIH Toolbox have ads?
Neither King nor NIH Toolbox shows ads.
Which is updated more often, King or NIH Toolbox?
King ships an update every 19 months, and NIH Toolbox every 4 months. Most recently, King was updated on October 7, 2026 and NIH Toolbox on October 7, 2026.

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