How do I get started?

Start with the free TDEE calculator at https://nanorhino.com/tdee — a 5-minute AI interview (no app, no account) that gives you the calories you actually burn plus a starter plan. Then put it to work with a coach in your messaging app: WhatsApp is the easiest way in, and it also works over SMS in the US. Already know your numbers? Head to https://nanorhino.com/message and pick WhatsApp to jump straight in.

Do I need to download an app?

No. NanoRhino lives in your messaging app — WhatsApp is the easiest way in, and it also works over SMS. We also offer an optional iOS app for users who prefer it, but it's not required.

Is there a message limit? What does it cost?

Messaging NanoRhino is free for up to 50 messages per day. On SMS, standard carrier message and data rates may apply. If you exceed your daily free allowance, additional usage fees may apply — we'll always notify you before any charge.

How do I unsubscribe?

Reply STOP at any time to unsubscribe. Reply HELP for assistance. You can re-enroll anytime by texting START again.

What is Link Heart Limited?

Link Heart Limited is an AI health technology company based in Houston, Texas. We build NanoRhino, an AI-powered weight loss companion that provides personalized nutrition coaching with a unique pay-for-results model.

NanoRhino is an AI weight loss coach. Think of it as a personal AI nutritionist, AI dietitian, and AI calorie counter rolled into one. It starts with a free TDEE calculation, turns that into a personalized plan, and then coaches you right in your messaging app — answering questions, logging meals you send or photograph, and adjusting as you go. No app required. You only pay $10 per pound you actually lose.

Is NanoRhino a free AI weight loss coach?

Texting NanoRhino is free for up to 50 messages per day, and you only pay if you actually lose weight — $10 per pound, capped at $500 total. There's no subscription, no upfront fee, and no charge if the weight doesn't come off. So functionally it's a free AI weight loss coach until you get results, then it's a results-based fee.

How does pay-for-results pricing work?

NanoRhino charges $10 per pound you lose, capped at $500 total — and that's the entire model. Three rules protect you. One: you only pay for confirmed loss — a pound counts once it's off and has stayed off for two weeks, so water-weight swings never trigger a bill. Two: the same pound is never billed twice — we bill against your lowest confirmed weight, so if some weight comes back and you lose it again, the re-loss is free. Three: no progress, no charge — plateaus cost nothing, and there's no subscription running in the background. If you don't lose weight, you never pay a cent. Billing questions anytime: support@nanorhino.com.

What if I regain some weight — do I ever pay for the same pounds twice?

Never. We track your lowest confirmed weight, and only pounds below it are ever billed. Say you start at 200 lb and reach 190: that's 10 pounds, $100, and 190 becomes your billing floor. If you bounce to 195 and work back down to 190, those 5 pounds are free — you already paid for them once. Nothing new is billed until you go below 190. This is deliberate: much of the weight-loss industry makes its money from the regain-and-restart cycle. We only earn on new progress — it keeps us on your side of the scale, not across from it.

Is NanoRhino private and secure?

Yes. NanoRhino is a private, judgment-free space — your conversations live in your messaging app. There are no social feeds, no posting, and no sharing. Your health data is encrypted, never sold, never shared with third parties, and never used for advertising. You can request deletion of all your data at any time.

How is NanoRhino different from other weight-loss tools?

Most apps make you tap through screens to log calories or follow generic meal plans. NanoRhino is a conversation: text a meal photo and get a calorie estimate back; vent about a hard day and get coached through it. It's like having a private nutrition coach on speed dial — at a fraction of the cost.

How is NanoRhino different from apps like MyFitnessPal or Cal AI?

Apps like MyFitnessPal and Cal AI are trackers — they tell you the calories in your meal and stop there. NanoRhino logs meals too (send or photo a plate in chat), but the product is the coaching: it sets your targets, checks in weekly, explains why the scale moved, and adjusts your plan — and you only pay when you actually lose weight ($10 per pound, capped at $500). See the full breakdowns: NanoRhino vs MyFitnessPal, NanoRhino vs Cal AI, or browse all comparisons.

How is NanoRhino different from ChatGPT or other general AI assistants?

Three reasons. First, NanoRhino remembers everything you've told it — goals, allergies, last week's wins, your hard days. ChatGPT loses that context across conversations. Second, NanoRhino does the math reliably — calorie counts, macro targets, weekly weight-loss math — without the arithmetic slips a general model makes. Third, NanoRhino is purpose-tuned to be a non-judgmental coach. A general AI tries to be helpful, but it isn't designed to meet you consistently in cravings, shame, or setbacks the way a real coach should.

Where is Link Heart Limited located?

Link Heart Limited is headquartered in Houston, Texas, United States.

Begin

Message your AI
weight-loss coach.
Pick a channel.

NanoRhino is your AI nutrition and weight-loss coach that lives in your messaging app — just chat, send a meal photo, and get your macros back. WhatsApp is the best way in. It also works over SMS in the US at (915) 277-7888. iMessage and RCS are coming soon — drop your email and we'll let you know the moment your channel opens up.

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chat with your coach — send a photo, get macros back

Open WhatsApp

SMS

Also available

(915) 277-7888

text START to begin · US only

Open Messages

iMessage

Coming soon

Coming soon. Get notified when it goes live.

RCS

Coming soon

Coming soon. Get notified when it goes live.

— Your first text can be this simple —

Weigh it 182.0

Logged ✓ 182.0 lb Nice drop — down from 184.7 last Friday, and that's four weeks running in the right direction. Keep this pace up and the trend stays strong. 💪

Verbatim from a real member's thread. See more real conversations →

How to message NanoRhino, by channel

SMS — live now in the US

Text the word START to (915) 277-7888 from any US mobile phone. The AI replies in seconds with a short onboarding — no app to download, no account to create. NanoRhino SMS coaching is free for up to 50 messages per day; standard carrier message and data rates may apply. Reply STOP to unsubscribe at any time or HELP for assistance.

SMS consent

By texting START to (915) 277-7888, you agree to receive recurring AI nutrition-coaching and reminder text messages from NanoRhino. Message frequency varies (up to 50 messages per day). Message & data rates may apply. Reply STOP to unsubscribe at any time or HELP for help. Your mobile opt-in and phone number are never shared with third parties for marketing. See our Privacy Policy and Terms of Service.

WhatsApp — live now

Message NanoRhino on WhatsApp from anywhere in the world over Wi-Fi or mobile data. Tap the WhatsApp option above to open a chat and say hi — the AI replies in seconds with a short onboarding, no app to download beyond WhatsApp itself and no account to create.

iMessage — coming soon

iMessage delivers your NanoRhino conversations as encrypted blue-bubble threads on iPhone, iPad, and Mac. Photos and receipts arrive at full resolution, so meal logging is sharper than SMS. Join the iMessage waitlist above and we'll alert you on launch day.

RCS — coming soon

RCS is the modern upgrade to SMS on Android — richer messages, read receipts, and full-resolution photos over your data connection. The NanoRhino RCS channel will offer the same coaching, photo calorie counts, and meal logging as SMS, with a nicer chat experience. Add your email above to be notified when it goes live.

Frequently asked questions

Which channel should I pick to message NanoRhino?

WhatsApp and SMS are both live today. On WhatsApp, message NanoRhino from anywhere in the world. On SMS, text START to (915) 277-7888 from any US phone. Either way the AI replies in seconds. iMessage and RCS are on the roadmap; leave your email and we'll notify you the moment they go live.

What is NanoRhino's phone number?

NanoRhino's SMS number is (915) 277-7888. The service is US-only at launch. Text the word START to begin — no signup, no account, no app.

When will iMessage and RCS be available?

We don't publish a fixed launch date, but if you join the waitlist on this page we'll email you the day your channel opens. iMessage and RCS will work exactly like WhatsApp and SMS once they launch.

Will my plan transfer when I switch channels?

Yes. Your coach remembers your goal, history, and preferences across channels — you won't have to start over when iMessage or RCS go live.

What information do you store from the waitlist form?

Only your email address, the channel you asked about, and a short traffic-source tag (if your link had one). We use it once — to notify you at launch — and never sell, share, or use it for advertising.

We'll only email you about the channel you picked. Reply STOP on SMS to unsubscribe; reply HELP for assistance. Standard carrier rates may apply.