Kidney Lens. The renal diet, seen honestly.
On a kidney diet, a confidently wrong number is worse than no number. Kidney Lens shows potassium, phosphorus, sodium and protein as ranges it can stand behind — and when it can't be sure, it says so instead of guessing.
Built for people already diagnosed with CKD: photograph a plate and see honest nutrient ranges from public government data, tracked against the targets your renal dietitian set. Its phosphorus-additive lens makes missing label evidence visible, it logs fluid and binders without ever suggesting an amount, and it builds a clinician-ready report. It never judges a food, never sets your limits, and never gives medical advice.
The kidney-diet app that tells you the truth.
Ranges, never fake precision
Every nutrient reads as a range with a stated basis — never a single fake-precise number. The milligrams come from USDA FoodData Central, the public-domain U.S. government nutrient database; Nora AI only reads your photo and estimates the portion, shown as a range too. What it estimates is labeled as an estimate, always.
It abstains instead of guessing
An unmatched food gets a question, not a fabricated estimate. A missing database value reads "not available" — never a false zero. And when confidence is low, Kidney Lens widens the range or asks you to confirm rather than printing a number it can't stand behind. A wrong "low potassium" is the one mistake this category can't afford.
A clear phosphorus-additive lens
Phosphorus isn't a required label nutrient, and the phosphate added to processed, branded and restaurant food is absorbed almost completely — yet it's invisible to nutrient tables. Instead of a falsely low number, Kidney Lens withholds it and flags: additive phosphorus likely — check the ingredient list for "PHOS." This safety evidence is available to everyone.
Your dietitian's targets, not ours
Potassium and phosphorus needs are individual — set by your renal dietitian from your blood tests. Kidney Lens tracks your day against the targets you enter, as calm neutral rings, and never asserts a cap of its own. Over a target? Today’s breakdown traces the foods that drove it — never an alarm.
Fluid, binders and meds — log only
Log fluid against a cap you enter, including the hidden liquids that count (soup, gelatin, ice cream, melon). Record binders and medicines taken with a meal. Kidney Lens remembers what happened; it never suggests an amount, a schedule, or a dose — those belong with your care team.
A report your clinician can use
Generate an appointment-ready report from your logs, built on your device: bands and explicit "withheld" cells, never false precision, with a non-diagnostic note on every page. Free includes a watermarked 7-day report; Pro unlocks the full-range, un-watermarked version your nephrologist or dietitian can actually work from.
One scan, told straight.
Banana, raw
Matched · portion 100–140 gA photo can't weigh a portion, so the portion is a range — and every milligram traces to USDA FoodData Central (bananas, raw — FDC ID 173944), the public-domain U.S. government nutrient database. Never a model's guess. One tap lets you correct an estimate before you save it locally.
Honesty is the feature
Kidney-diet apps love confident numbers — an exact potassium count from a photo, a "0 mg" where the database simply had a gap. On a renal diet, confidently wrong isn't just wrong; it's the one mistake the category can't afford.
Kidney Lens shows the range it can stand behind, widens it when it's less sure, and abstains rather than guessing. A missing value reads "not available" — never a false zero.
Phosphate additives in processed food are absorbed almost completely and don't appear on nutrition labels. So instead of a falsely low number, Kidney Lens withholds the number and points you to the ingredient list.
And it never plays clinician: no food verdicts, no app-set potassium or phosphorus limits, no binder or fluid instructions, no reading of your labs. Your renal dietitian sets the targets; Kidney Lens tracks against them.
The honest range, every time. That's the whole app.
Honest tracking, free. Pro for the depth.
The tracker is genuinely useful from day one — no quiz walls, no pay-before-you-see-it, and nothing you need to stay safe behind a paywall. Kidney Lens Pro sells depth, never "unlock your care."
- 1 signed-in photo scan a day with honest bands
- Unlimited manual & barcode logging
- Day rings against your own targets + today’s breakdown
- Fluid, binder & medication logs
- 7-day history & the cited education library
- Watermarked 7-day clinician report
- 10 signed-in photo scans a day
- Save, compare & re-log meal scenarios
- Full 7 / 30 / 90-day nutrient trends
- Full-range, un-watermarked clinician report
Local-first, and it stays that way.
Your logs live on your device
Kidney Lens is local-first: your food, fluid, medication and target logs are stored on your iPhone. There's no cloud copy of your diary, no account needed to track, and you can export your data on-device anytime.
Your meal photo isn't kept
A scan photo is used only in memory and is never stored on our servers. The current version does not keep scan-correction records on our servers or use them to personalise later photo scans. A confirmation can be saved with your local log; neither the photo nor optional note is retained in the Kidney Lens app database after the scan.
Consent, per provider and purpose
The photo scan runs only after your separate, explicit consent. You can withdraw it at any time; that blocks future requests across your signed-in devices until you explicitly allow a new scan. The Privacy Policy identifies the current processor and what it receives.
No ads. No data sales.
No third-party advertising, no tracking SDKs, and your health information is never sold or shared for advertising. Billing is Apple StoreKit only — we never see your card. Delete your account and data from inside the app, anytime.
Questions, answered.
Does Kidney Lens tell me whether a food is safe to eat?
Never — and that's deliberate. What a food means for you depends on your stage, your blood tests, and the plan your renal dietitian set, so a one-word verdict from an app would be a guess dressed up as advice. Kidney Lens shows what's in the food as honest ranges, shows your running day against the targets you entered, and leaves the judgement where it belongs: with you and your care team.
Where do the nutrient numbers come from?
Every potassium, phosphorus, sodium and protein value comes from USDA FoodData Central — the public-domain (CC0) nutrient database published by the U.S. government. The app's AI, Nora AI, only identifies the dish in your photo and estimates the portion as a range; it never invents a nutrient number. If a food can't be matched to the database, Kidney Lens asks you instead of fabricating a plausible-looking estimate.
Why does phosphorus sometimes show a flag instead of a number?
Phosphorus is not a required nutrition-label nutrient, and the phosphate additives in many processed, branded and restaurant foods are absorbed almost completely — yet they're invisible to nutrient tables. A number would look reassuring and be wrong. So when additive phosphorus is likely, Kidney Lens withholds the number and shows a flag: additive phosphorus likely — check the ingredient list for "PHOS." An honest unknown beats a confident wrong answer.
Does Kidney Lens set my potassium or phosphorus limits?
No. Current kidney-nutrition guidelines (KDOQI 2020, KDIGO 2024) individualize potassium and phosphorus to your blood tests — there is no fixed number that's right for everyone, and your renal dietitian sets yours. Kidney Lens shows food content and tracks your day against the targets you enter from your dietitian's plan. It never asserts a limit of its own, and going over your target is shown as a neutral ring and a breakdown — never an alarm or a judgement.
What's free and what's Kidney Lens Pro?
Free forever: one signed-in photo scan a day with honest bands, unlimited manual and barcode logging, day rings against your own targets with today’s breakdown, fluid, binder and medication logs, 7-day history, the cited education library, and a watermarked 7-day clinician report. Ingredient-panel PHOS evidence and phosphorus withholding stay free. Kidney Lens Pro — $9.99/month or $59.99/year with a 7-day free trial on the annual plan — raises signed-in photo scanning to 10 a day and adds saved meal comparison and re-logging, full 7/30/90-day trends, and the full-range, un-watermarked clinician report.
Is Kidney Lens medical advice or a medical device?
No. Kidney Lens is a tracking and education companion for people already diagnosed with kidney disease by a clinician — it is not a medical device and not a source of medical advice. It does not diagnose CKD, interpret blood tests, judge foods, set personal nutrient limits, or give dose, binder, or fluid instructions. Its educational content is general and cited, and its numbers are ranges with a stated basis. Always talk to your renal dietitian, nephrologist or doctor before changing your diet, fluids or medicines.