Comparison

HemiStim vs Focus Builder Pro

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

Head to head
About

HemiStim

This app offers visual stimulation for specific brain lobes, aiding in hemispheric connectivity. It utilizes color patterns and eye-tracking exercises for targeted left or right brain stimulation, controllable via simple taps and swipes. Therapy sessions are automatically tracked and can be emailed to clinicians.

Highlights
  • Visual stimulation of frontal, parietal, occipital, temporal lobes
  • Hemispheric brain stimulation
  • Color pattern selection
  • Eye tracking for saccadic and pursuit movements
  • Adjustable blink rate and timer
  • Automatic therapy session tracking
  • Clinician-patient email communication
Features
Currently charting
Read full description

Hemistim can be used as a visual stimulation of areas of the frontal, parietal, occipital, and temporal lobes hemispherically. It is a specific brain stimulation which is rarely used in conjunction with other treatments but can be used as a portion of a home-based program or an office-based program. Such usage may lead to improved hemispheric connectivity specific, targeted areas of the brain and its connections to the parietal/temporal or frontal cortices. Hemistim provides a visual stimulation through utilizing color patterns and eye tracking that can be used for specific left or right visual exercise. The stimulus is recognized and  interpreted by the contralateral (opposite) occipital lobe. Pursuit and saccadic eye movements are created by targeting on the moving object. Pursuit away from and saccade towards the alternating squares are initiated by the ipsilateral (same side) parietal and frontal cortex, respectively.  This gives the doctor the ability to work the frontal, parietal, occipital, and temporal lobes hemispherically.  HemStim is easy to use. Swipe left or right to select a different colored pattern. Multiple patterns are available. Tap a pattern to make it begin blinking. The pattern will blink until the timer stops it. Double tapping the pattern will also make it stop. The blink rate and timer can be changed using the sliders. Target motion is controlled by the tapping the small target to the right of the speed control. Choose among no motion, saccade, and pursuit by successive taps on the small target. Exterior motion is indicated by purple arrows on the target and interior motion by white arrows. The new Saccades screen only displays target motion. Drag the purple target with one finger to set the direction and length of its motion. Tap the screen once simultaneously with two fingers to switch between saccades, a dashed line, and pursuits, a solid line. Tap the screen once with one finger to start the saccades or pursuits. Double tap the screen with one finger to stop the target motion. HemiStim automatically tracks therapy sessions, recording all pertinent information about each one. Maintain close communication between clinician and patient via email.

About

Focus Builder Pro

This app offers targeted eye movement exercises designed to enhance brain plasticity and neurotherapeutic outcomes. It provides customizable exercises and patient session building for practitioners, and permanent access to exercises for patients under guidance.

Highlights
  • Targeted eye movement exercises
  • Brain plasticity enhancement
  • Customizable exercise settings
  • Patient session builder
  • Progress monitoring
  • Neurotherapeutic outcomes
Features
Read full description

Focus Builder: Targeted Eye Movement Exercises for Functional Neurologists and Patients Focus Builder is an iPad-optimized app delivering evidence-based eye movement exercises to promote brain plasticity and neurotherapeutic outcomes. Access requires creating an account and selecting your role: Subscription & Access Details Focus Builder requires role selection upon signup: Practitioner (Functional Neurologist) or Patient. This choice is permanent. - For Practitioners: Auto-Renewing Subscription Unlocking: - Access to 12 exercises with lots of customizable settings. Create new exercises based on the settings + sequences of exercises. - Patient session builder: Create and assign personalized exercise sequences for your patients, including progress monitoring and adjustment based on outcomes. Subscriptions auto-renew via Apple and can be managed in your App Store account. No free trial, but full access starts immediately upon purchase. Cancel anytime. - For Patients: One-Time In-App Purchase Permanent access to all exercises under your practitioner's guidance. No ongoing fees—includes any sequences assigned by your doctor for personalized therapy or usage of the exercises. Payment details are shown in your user profile after login. Role selection is permanent and cannot be changed later. No free trial or limited access—full functionality begins after purchase. Eye movements are a very powerful way to exercise the brain and to create long-term change in the brain, known as plasticity. The “Focus Builder” app contains a variety of exercises which challenge users to voluntarily move their eyes in various patterns, speeds and directions, which have been proven to activate specific parts of the brain depending on which eye movement is performed. This app is specifically designed for doctors that specialize in Functional Neurology and their patients. There is currently no app available that can provide these specific exercises. For best results, patients should consult a Functional Neurologist to determine how to use this app according to their needs and obtain the most therapeutic value. There are 3 types of eye movements that can have profound therapeutic benefits and all three are available in this app. 1.Pursuits (slow eye movements): Smooth pursuit eye movements allow the eyes to closely follow a moving object. Most people are unable to initiate pursuit without a moving visual signal. The pursuit of targets moving with velocities of greater than 30°/s tend to require catch-up saccades. 2.Saccades (fast eye movements): Saccades are quick, simultaneous movements of both eyes in the same direction. Initiated cortically by the frontal eye fields (FEF), or subcortically by the superior colliculus, saccades serve as a mechanism for fixation, rapid eye movement, and the fast phase of optokinetic nystagmus. 3.Anti-saccades (look away): The anti-saccade task has emerged as an important task for investigating the flexible control that we have over behavior. In this task, participants must suppress the reflexive urge to look at a visual target that appears suddenly in the peripheral visual field and must instead look away from the target in the opposite direction. A crucial step involved in performing this task is the top-down inhibition of a reflexive, automatic saccade. Patients diagnosed with various neurological and/or psychiatric disorders that affect the frontal lobes or basal ganglia find it difficult to suppress the automatic pro-saccade, revealing a deficit in top-down inhibition. The areas of the brain that are activated by these eye movements are too numerous to list, but to name a few, I have listed some of the functions that can improve with these eye exercises. 1.Executive function/behavior 2.Attention 3.Concentration 4.Impulse control 5.Social behavior 6.Motivation 7.Goal directed behavior Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

HemiStim3 screens
Focus Builder Pro4 screens

Verdict

The call

The clearest difference is price: Focus Builder Pro at Free against HemiStim's $9.99. Focus Builder Pro also leads on rating (5.0 vs 2.4) and update cadence (every 10 days vs every 8 months). HemiStim's advantage is review sentiment (38% vs 0%) and in-app purchases (none vs 3). On 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

Focus Builder Pro is free to download; HemiStim costs $9.99 up front. Focus Builder Pro sells 3 in-app purchases, starting at $9.99 per month. HemiStim asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Focus Builder Pro holds the better App Store score, 5.0 against 2.4. Both are backed by a comparable volume of ratings — 5 and 2 respectively. Written reviews complicate that: 38% of HemiStim's written reviews are positive against 0% of Focus Builder Pro's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

HemiStim ships an update every 8 months, Focus Builder Pro every 10 days. The most recent releases landed on September 14, 2026 and September 13, 2026 respectively.

Scorecard8 real differences · 3 level
HemiStim versus Focus Builder Pro: the parameters behind the verdict, then further details
ParameterHemiStimFocus Builder Pro
Price$9.99Free — better
Rating2.4 (5 ratings)5.0 (2 ratings) — better
Positive reviews37.5% of reviews — better0.0% of reviews
Number of ratings5 — better2
Update frequencyEvery 8 monthsEvery 10 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFreemium — better
Best chart rank#196 — better
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS12.0 — better15.1
Further details — not scored
Size1 MB50 MB
Age rating4+17+
DeveloperLinsay Associates, LLCNeurdSolutions, LLC

Customer experience

HemiStim

All ratings5 ratings
Positive40.0%
Neutral0.0%
Negative60.0%
Written reviews8 reviews
Positive37.5%
Neutral12.5%
Negative50.0%

Focus Builder Pro

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

In-app purchases

None

HemiStim

No in-app purchases

3 purchases

Focus Builder Pro

Subscriptions2
  • Focus Builder Pro Practitioner$9.991 Month
  • Focus Builder Pro Practitioner$69.991 Year
One-time1
  • Patient Purchase$19.99

Questions

Is HemiStim free?
HemiStim costs $9.99, with no in-app purchases.
Is Focus Builder Pro free?
Focus Builder Pro is free to download, with in-app purchases available.
Which has better reviews, HemiStim or Focus Builder Pro?
Focus Builder Pro is rated higher. HemiStim averages 2.4 out of 5 from 5 ratings, while Focus Builder Pro averages 5.0 from 2 ratings.
Do HemiStim or Focus Builder Pro have ads?
Neither HemiStim nor Focus Builder Pro shows ads.
Which is updated more often, HemiStim or Focus Builder Pro?
HemiStim ships an update every 8 months, and Focus Builder Pro every 10 days. Most recently, HemiStim was updated on September 14, 2026 and Focus Builder Pro on September 13, 2026.

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