Comparison

NASA PVT+ vs Ballpark

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

Head to head
About

NASA PVT+

This app provides a validated tool for conducting psychomotor vigilance tests, crucial for sleep, alertness, and performance research. It offers multiple study frameworks, including simple tests, basic multi-day studies, and specialized aviation research protocols.

Highlights
  • Psychomotor Vigilance Test (PVT)
  • Karolinska Sleepiness Scale (KSS)
  • Sleep Diary
  • Simple PVT mode
  • Basic Study framework
  • Aviation Study framework
Features
Read full description

The official NASA PVT+ (Psychomotor Vigilance Test) is a validated iOS based touchscreen PVT that includes multiple industry standard research forms for collecting a wide range of research data for sleep, alertness and performance studies. The app has three principle data collection schemes designed to accomidate a wide range of research studies. The Simple PVT: The Simple PVT is a single presentation of the Psychomotor Vigilance Test (PVT; described below). Participants can be instructed to take a PVT at any time. There is no limit to the number of PVTs that a participant can take. Basic Study: The Basic Study provides a single or multiday pre-set framework for collecting research data. Participants are prompted to complete a sleep diary after their main sleep episode. The participant is then prompted to complete three PVT and Karolinska Sleepiness Scale (KSS) responses during the day. The participants also complete a sleep diary before bed. Aviation Study: The Aviation Study provides a multiday pre-set framework for collecting aviation related research data. Split into Off-Duty Days and Duty Days. Participants are prompted to complete a sleep diary after their main sleep episode. The participant is then prompted to complete three PVT and KSS responses during off-duty days. On duty days, the participant is prompted to complete a PVT and KSS pre- and post-duty. They are also prompted to complete a PVT, KSS, hassle factors, use of fatigue countermeasures, and inflight rest at the top of descent for each flight. The participants also complete a sleep diary before bed. The number of flights within a duty day can be adjusted. The aviation study also includes a pre-study baseline questionnaires that can be completed at study enrollment. The specific components of the application include: - Psychomotor Vigilance Test (PVT): A simple reaction-timed test that is sensitive to sleep loss and circadian misalignment. The PVT displays a box on the screen and participants are instructed to tap the screen with their dominant thumb when a millisecond counter appears in the box and begins to count up. After the participant taps the screen, the counter briefly displays the reaction time in milliseconds, then the counter disappears, and the participant is instructed to refrain from touching the screen until the next millisecond counter appears in the box. The counter appears randomly every 2 to 10 seconds. The PVT can be configured by the investigator to the desired duration (currently validated for a 5-minute test). - Karolinska Sleepiness Scale (KSS): The KSS is a self-reported sleepiness rating where the participant is asked to rate their level of sleepiness within the last five minutes on a scale from 1 to 9. - Sleep Diary: The Basic Study and Aviation Study each include a sleep diary that the study participant is prompted to complete at the beginning and at the end of the main sleep episode. The pre-sleep sleep diary asks the participant to record any naps that were taken prior to the main sleep episode, along with indicating the time of bedtime. The post-sleep sleep diary asks the participant to record the time that it took to fall asleep, number and duration of night awakenings, final wake time, and a sleep quality rating. - Study Enrollment Information: The Aviation Study includes a demographic questionnaire and the Morningness-Eveningness Questionnaire along with a practice sleep diary and practice PVT to orient the participant to study procedures. Data collected from study participants using the NASA PVT+ iOS application does not include Personally Identifiable Information (PII). Research data is never collected directly by NASA unless a volunteer is participating in a NASA study. Data collected for research studies conducted outside of NASA, through use of the NASA PVT+ application, is never sent to NASA without a specific agreement between the outside organization and NASA.

About

Ballpark

Features
Read full description

Ballpark is a simple, flexible macro tracker built for real life, not perfect precision. LOG MEALS YOUR WAY Write what you ate in your own words, add a photo, or use your voice. Ballpark AI creates an approximate meal entry with calories and macros for you to review and adjust before saving. Prefer full control? Manual meal tracking is always available for free. FLEXIBLE GOALS, USEFUL CONTEXT Set only the calorie and macro ranges that matter to you, or skip goals entirely. Ballpark gives you a clear daily overview and helps you follow longer-term trends without treating incomplete tracking days as complete data. FEATURES • Track calories, protein, carbohydrates, and fat • Log meals manually or from natural-language descriptions • Add meal photos or nutrition labels for context • Use voice input and written clarifications • Review and edit every AI estimate before saving • Set optional minimum and maximum goals • Get suggested starting goals from basic personal details • Save favorite meals and quickly reuse recent entries • View weekly, monthly, six-month, and yearly trends • Mark incomplete days for more meaningful averages • Optionally sync weight from Apple Health to track weight trends on your device • Set meal reminders • Export meal data and create local backups • Choose metric or imperial units • Available in English, German, French, Italian, Spanish, and Russian DESIGNED FOR CONSISTENCY Nutrition tracking does not need to be perfectly precise to be useful. Ballpark focuses on reasonable estimates, visible assumptions, and easy corrections, so tracking can fit into everyday life. PRIVACY AND CONTROL Your tracking data is stored locally on your device, and no account is required. You decide whether to use AI processing, photos, voice features, or Apple Health integration. When you use Ballpark AI, the information needed for your request is sent through Ballpark’s backend to OpenAI for processing. Apple Health weight data is read-only, remains stored locally in Ballpark, and is never sent for AI processing. BALLPARK AI Manual tracking, history, trends, exports, and access to existing data remain available without a subscription. Ballpark AI is available through a monthly auto-renewable subscription. It adds AI-powered meal estimates, photo logging, and the option to refine estimates by voice. Estimates are approximate and should always be reviewed before saving. Privacy Policy: https://nickburri.github.io/ballpark-site/privacy.html Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

NASA PVT+4 screens
Ballpark4 screens

Verdict

The call

The clearest difference is in-app purchases: NASA PVT+ at none against Ballpark's 1. NASA PVT+ also leads on device support (3 vs 1) and iOS requirement (13.6 vs 17.2). Ballpark's advantage is update cadence (every 3 weeks vs every 3 months). On price and ads 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. Ballpark sells 1 in-app purchase, starting at $1.99 per month. NASA PVT+ asks for nothing beyond the download.

UpkeepUpdate frequency

NASA PVT+ ships an update every 3 months, Ballpark every 3 weeks. The most recent releases landed on November 2, 2026 and November 10, 2026 respectively.

Scorecard4 real differences · 6 level
NASA PVT+ versus Ballpark: the parameters behind the verdict, then further details
ParameterNASA PVT+Ballpark
PriceFreeFree
Rating4.8 (10 ratings) — better—
Positive reviews25.0% of reviews—
Number of ratings10 — better—
Update frequencyEvery 3 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone
Requires iOS13.6 — better17.2
Further details — not scored
Size31 MB3 MB
Age rating4+4+
DeveloperNASANICK BURRI

In-app purchases

None

NASA PVT+

No in-app purchases

1 purchases

Ballpark

Subscriptions1
  • Ballpark AI7 Days trial$1.991 Month

Questions

Is NASA PVT+ free?
NASA PVT+ is free to download, with no in-app purchases.
Is Ballpark free?
Ballpark is free to download, with in-app purchases available.
Do NASA PVT+ or Ballpark have ads?
Neither NASA PVT+ nor Ballpark shows ads.
Which is updated more often, NASA PVT+ or Ballpark?
NASA PVT+ ships an update every 3 months, and Ballpark every 3 weeks. Most recently, NASA PVT+ was updated on November 2, 2026 and Ballpark on November 10, 2026.

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