StackSnap — your supplement shelf, audited.

Four categories of avoided cost:

• Duplicate ingredients — two supplements containing overlapping active ingredients (your multivitamin has magnesium and you also take a separate magnesium glycinate)
• Potential overdoses — amounts above tolerable upper intake levels (16,000% RDA of B12 across your B-complex plus a separate B12 sublingual)
• Low-quality brand premium — where you pay significantly above U.S. median for the same ingredient
• Supplements with no published evidence for the stated benefit

The dollar number reflects what the average user could redirect by acting on findings. Actual savings depend on which supplements you choose to discontinue or replace — StackSnap shows the information, you make the call.

StackSnap uses RxNav — the National Library of Medicine's drug interaction reference database. Same dataset pharmacists consult.

Interactions are based on documented mechanisms: cytochrome P450 effects (drugs metabolized through liver enzymes), absorption competition (iron vs calcium), blood-thinning additivity (fish oil + warfarin), blood-pressure compounding (potassium + ACE inhibitors), etc.

This is a screening tool, not a medical diagnosis. Always confirm any flagged interaction with your pharmacist or doctor before changing any supplement or medication.

The NIH Dietary Supplement Label Database (DSLD) is a U.S. National Institutes of Health database indexing over 130,000 supplement product labels with verified ingredient amounts and source citations.

StackSnap pulls scan results directly from DSLD rather than using proprietary "TrustScore" systems that change without explanation. Every ingredient you see has a documented government-database source — verifiable in the public NIH database.

No. StackSnap is a general wellness app designed to help organize and understand your supplement routine. It is not a medical device, is not FDA-cleared as such, and does not provide medical advice, diagnosis, or treatment recommendations.

Always consult a qualified healthcare professional — your doctor, pharmacist, or registered dietitian — before starting, stopping, or changing any supplement or medication. Do not disregard professional medical advice based on information from this app.

No. StackSnap is an organizational and informational tool, not a recommendation engine.

It tells you what you are taking, what overlaps exist, what amounts are above standard upper intake levels, and what interactions might exist with your prescriptions. It does not tell you what you should take — that's a decision to make with your doctor or registered dietitian.

Broadly: anything indexed in NIH DSLD.

• Vitamins — A, B-complex (B1, B2, B3, B5, B6, B7, B9, B12), C, D, E, K
• Minerals — calcium, magnesium, zinc, iron, selenium, chromium, iodine, potassium
• Amino acids — L-theanine, glutamine, taurine, BCAAs, lysine, tryptophan
• Herbals — turmeric, ashwagandha, ginkgo, milk thistle, rhodiola, ginger
• Nootropics — Alpha-GPC, Lion's Mane, Bacopa, Phosphatidylserine, Citicoline
• Other — omega-3s, probiotics, protein powders, pre-workout supplements, sleep aids (melatonin, valerian, L-tryptophan), adaptogens

Yes. RxNav covers FDA-approved prescription medications and their documented interactions with supplements and other drugs.

Add your prescriptions once (input by drug name or scan the prescription label), and StackSnap automatically cross-references them whenever you scan a new supplement.

A clean 1-page PDF summary of every supplement in your stack: brand, ingredient, daily amount, timing, any flagged interactions or potential overdoses.

Use before any healthcare provider visit:

• Primary care annual exams
• Endocrinologist visits
• Pharmacist consultations
• Naturopath sessions
• Pre-op consultations (some supplements affect bleeding and anesthesia)

Saves 5–10 minutes of fumbling through bottles and gives your provider real information to work from.

Yes. Smart reminders organize by recommended timing:

• Fat-soluble vitamins (A, D, E, K) — with the largest meal
• Magnesium glycinate — at night for sleep support
• B-complex — morning, away from caffeine
• Berberine — with carb-heavy meals
• Melatonin — 30 minutes before sleep
• Iron — away from coffee and dairy

All reminders are customizable. You can set per-supplement schedules.

Identical features. Weekly is $4.99/week (best for short-term tracking during a new health protocol or supplement experiment). Annual is $39.99/year (saves over 84% vs weekly). For most users who scan their stack once or twice a month and review interactions periodically, annual is the better economic choice — most users identify more than $39.99 in savings in the first month alone.

All subscriptions managed through Apple. To cancel:

1. Open Settings
2. Tap your Apple ID at the top
3. Tap Subscriptions
4. Find StackSnap → tap Cancel Subscription

Takes effect at end of current billing period. The 7-day trial can be cancelled any time before it ends with no charge.

StackSnap uses SwiftData local-first storage — your supplement stack data is stored on your iPhone first, with iCloud sync optional.

Anonymous scan metadata may be used to improve the AI model. Health-related data is never shared with third parties or used for advertising. Full privacy policy: love8ko.github.io/stacksnap/privacy-policy.html.

No. Your scanned stack data persists locally on the device even after cancellation or sign-out (unlike Care/of, Prove It, and similar apps that wipe the stack on logout).

You retain read access to historical scans, the doctor PDF feature, and your stack list — but lose access to new scans, the interaction checker, and ongoing reminders unless you resubscribe.

Coverage is strongest for U.S.-marketed brands indexed by NIH DSLD. For European, Australian, or Asian brands not in DSLD, you can manually enter the ingredient list and StackSnap will check it against the same overlap and interaction logic.

The NIH database keeps growing — coverage improves over time.

No. Counterfeit detection requires lab testing of the contents. StackSnap reads the label and the database entry, not the actual substance in the bottle.

For verifying authenticity of expensive or rare supplements, third-party testing (LabDoor, ConsumerLab) is necessary. StackSnap can flag suspicious patterns (unusually low price for a high-end ingredient, unlisted manufacturer) but cannot confirm or rule out counterfeits.

StackSnap is designed for adult supplement tracking. Pediatric dosing has different upper intake limits, age-specific interaction profiles, and considerations that StackSnap is not specifically calibrated for.

The doctor PDF feature still works for organizing the list for pediatric visits — but always consult a pediatrician for dosing or interaction questions specific to children.

Yes. StackSnap integrates with Apple HealthKit so your supplement schedule and adherence can sit alongside your other health data (workouts, sleep, prescriptions). HealthKit integration is optional and can be enabled or disabled in Settings.

You see an alert with:

• Specific mechanism — e.g. "St. John's Wort accelerates the metabolism of many medications via CYP3A4 induction, potentially reducing efficacy"
• Severity classification — theoretical, mild, moderate, severe
• Recommendation — consult your pharmacist or doctor before making any changes

Never stop a prescribed medication based on a StackSnap flag — always speak to your prescribing physician first. The flag is the AI noticing a documented risk; the clinical judgment about what to do is your healthcare provider's.

SuppCo (18,780 App Store reviews) shows proprietary TrustScores that fluctuate without explanation. StackSnap shows you dollar-savings from your specific stack plus the underlying ingredient data sourced directly to NIH DSLD entries.

Prove It (13,842 reviews) is currently struggling with 83% of recent reviews rating 1 star — primarily due to dark-pattern paywall complaints and absence of a real free trial.

StackSnap is built specifically as the honest alternative: full Pro access during the 7-day trial, no quiz, transparent pricing, RxNav interaction checks, doctor PDF export.

7-day free trial with full Pro access. No 20-question quiz before you see the app, no email signup gate, no credit card required upfront.

After trial:

• Weekly: $4.99/week
• Annual: $39.99/year (saves over 84% vs weekly billing)

Cancel in two taps via Settings > Apple ID > Subscriptions. No quiz, no email gate, no surprise charges.