Digital health · AI symptom companion
Juno
A chat and voice app that asks people with chronic illness how they feel, logs the answer, and turns weeks of messy symptom notes into a summary for the next doctor's appointment. Built by two recent university graduates, it has grown fast on organic downloads and is now the newest company in Y Combinator's Spring 2026 batch.
"My migraine is 7 out of 10"
That is the example the company itself gives for how Juno is supposed to work. A user with a chronic condition texts or talks to the app the way they would message a friend, and Juno pulls a symptom, a severity score and a time stamp out of the sentence without asking them to fill in a form. Over weeks, those small entries build into a timeline: what flared, what came before it, what the person's sleep and wearable data were doing at the time.
The app also offers what the company calls a calm, non-judgmental space for a bad day, and turns months of notes into a PDF a patient can hand to a doctor at the start of a short appointment.
1 billion people, a 7.6 year wait
The company's pitch rests on a specific number. More than a billion people worldwide live with a chronic illness, the founders say, and the average diagnosis takes 7.6 years to arrive. Conditions named on the app's own marketing, on the App Store listing and on Google Play read like a list of the chronically under-served: fibromyalgia, long COVID, POTS and dysautonomia, ME/CFS, Ehlers-Danlos syndrome, endometriosis, lupus, mast cell activation syndrome, and other conditions that are hard to see on a scan and easy to dismiss in a short appointment.
Juno's answer is not a diagnosis. The FAQ is explicit that the app "doesn't diagnose conditions or tell you what your symptoms mean" and that only a clinician can do that. What it offers instead is documentation: a structured record built from ordinary conversation, plus wearable data from more than twenty platforms including Apple Health, Oura, Garmin, Fitbit and Whoop, layered against context such as weather and pollen counts to suggest patterns worth raising with a doctor.
Two UCL students, one earlier start that did not work
Isaac Tolley and Marshall Gould met at University College London, where Tolley studied for an MSc in Bioscience Innovation and Enterprise and Gould for a BSc in Genetics. Both have chronic conditions of their own. Tolley has said he grew up with chronic sinusitis, and in the company's own account he "waited 14 years for an eosinophilic bronchitis diagnosis." Gould lives with ME/CFS. On the app's own story page, an unnamed founder describes the onset in blunter terms: fevers, tonsillitis and sinus headaches in the first weeks of university that did not go away, mistaken at first for ordinary student tiredness.
Juno was not their first attempt to build something for this. Through UCL's Venture Builder programme, the pair first built SharedGenes, described by UCL as "a social network to connect people with rare and chronic diseases." They did not take it forward. Isaac Tolley has said the experience was still valuable, calling it "an important stepping stone in propelling us forward in our entrepreneurial journey." The name has not disappeared, though: Apple's App Store listing for Juno carries the copyright line "2025 SharedGenes," and the app's seller of record on Apple's platform is Marshall Gould. The consumer brand is Juno. The legal entity behind it, on the available public listing data, still carries the earlier company's name.
From a UCL programme to a YC batch
The company says it launched in October, without specifying the year in the copy the founders published on Y Combinator's site, though the surrounding context points to October 2025. From there the growth numbers climb quickly and inconsistently across sources. A Product Hunt launch attributed to Marshall Gould, dated to around February 2026, put the app at "125,000+ patients globally" and "$80K MRR." Six months after launch, the founders' own Y Combinator batch post counted a more conservative 80,000 users and "9,000+ five-star App Store reviews." By July 2026, UCL's press office, writing about the pair's acceptance into the accelerator, cited "150,000 times" downloaded and 15,000 five-star reviews. A later crawl of the Y Combinator company page put the figure at "300,000+ patients globally." None of these figures share a dated, common methodology.
The accelerator relationship itself is verifiable. Juno is listed as an active company in Y Combinator's Spring 2026 batch, a two-person team with David Lieb as primary partner. UCL's press office reported the standard terms of that investment: "$500,000 for 7% equity," plus mentorship and a demo day in San Francisco. That is Y Combinator's standard deal, not a number specific to Juno, and it is the only funding figure that traces to a named, checkable source.
What is proven, and what is still claimed
| Evidence | What the record shows | Source type |
|---|---|---|
| Founders and prior venture | Isaac Tolley and Marshall Gould, UCL alumni, previously built SharedGenes, a social network for people with rare and chronic disease, through UCL's Venture Builder programme before starting Juno. | Independent |
| Legal entity behind the app | Apple's App Store listing shows copyright "2025 SharedGenes" and lists Marshall Gould as the seller. The consumer brand Juno and the earlier company SharedGenes appear to be the same legal entity, or a closely related one. | Public record |
| User and download figures | Self-reported totals range from 80,000 users (six months post-launch) to 125,000, 150,000 and 300,000-plus across different company channels and dates, with no consistent methodology given. | Differs across sources |
| Pricing | The company FAQ states a single price, $19.99 a month or $99.99 a year. The Apple App Store listing shows multiple concurrent price points for the same subscription, from $4.99 to $19.99 a month and $39.99 to $99.99 a year. | Differs from FAQ |
| Clinical involvement | The FAQ says the knowledge base draws on medical journals and sources such as Mayo Clinic and Mount Sinai, with "input from hundreds of doctors" shaping the product. No named medical advisory board, clinician list, or study appears on the company's own site. | Not named |
| Regulatory and clinical trial records | No FDA clearance, PMA, registered clinical trial, NIH award or PubMed record tied to this company was found. Juno is marketed as a wellness and support tool, not a diagnostic or treatment device. | Not found |
| SEC filings | No Form D was found under Juno, Juno Chat, or SharedGenes in SEC EDGAR's company and full text search as of September 25, 2026, despite the reported $500,000 Y Combinator investment. | Not found |
| User community response | Multiple Reddit threads in r/ChronicIllness and r/Fibromyalgia carry titles flagging concerns about the app. Reddit's site blocked automated access during this research, so their content could not be independently read or quoted. | Unverified |
Read plainly: the product itself, a chat interface that logs symptoms and prepares appointment summaries, is well documented by the company and consistent across its own channels. The growth story attached to it is not. User counts move up and down across time in a way normal growth alone does not explain, pricing on the company's own storefront does not match its own FAQ, and no clinician, study or regulatory record backs the claim that hundreds of doctors shaped the product. That does not mean the app fails the people using it. It means the numbers behind it have not yet been made to add up.
What to watch
- Whether Juno files a Form D, or an amended one, now that it has completed a Y Combinator batch and gone through a public demo day.
- Whether the company publishes a consistent, dated user or subscriber count instead of the shifting figures seen across its own posts.
- Whether a named medical advisory board or any peer-reviewed evaluation of the app's guidance ever appears.
- What, if anything, comes of the user complaints referenced in Reddit thread titles, once that content can be read directly.
In their words
“So we wanted to build something that would help people both understand their health and have that support while you’re going through it as well.”
Isaac Tolley, co-founder, UCL News, July 2026 · Independent
“We started building Juno after growing up with chronic conditions ourselves.”
Isaac Tolley and Marshall Gould, co-founders, Y Combinator launch post · Company-stated
“Isaac waited 14 years for an eosinophilic bronchitis diagnosis. Marshall lives with ME/CFS and is still searching for something that helps.”
Isaac Tolley and Marshall Gould, co-founders, Y Combinator launch post · Company-stated
“It’s amazing to be part of this place that’s incubated so many successful businesses like AirBnB, Instacart and Coinbase.”
Isaac Tolley, co-founder, UCL News, July 2026 · Independent
“We’ve grown about 70% month on month so far, which we’re really proud of, but we want Juno to reach even more people.”
Isaac Tolley, co-founder, UCL News, July 2026 · Independent
“Isaac and Marshall have found a simple but powerful way to harness AI technology that’s now benefitting thousands of people struggling with long-term health conditions.”
Professor Geraint Rees, UCL Vice-Provost, UCL News, July 2026 · Independent
Related companies
Sources
- CompanyJuno company profile and launch post
- CompanyLaunch YC: Juno, AI Health Assistant for Chronic Illness
- IndependentUCL AI health startup selected for influential business accelerator
- CompanyJuno, Your 24/7 AI Health Assistant for Chronic Illness
- CompanyJuno FAQ, How the AI chronic illness health assistant works
- CompanyThe Juno story, built from chronic illness, for chronic illness
- Public recordJuno, Chronic Illness Support, app listing
- Public recordJuno, Chronic Illness Support, app listing
- CompanyWe just launched Juno, an AI clinical specialist for chronic illness
- Public recordSEC EDGAR company and full text search for Juno, Juno Chat and SharedGenes
- UnverifiedPSA about the Juno app (please read), this should make you angry
Profile researched and written by Healthcare Discovery. Last updated September 29, 2026.
