This article is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider for medical decisions.

TL;DR: Ada Health is a free AI symptom checker that helps you figure out what might be causing your symptoms. It is the most accurate symptom checker tested in a peer-reviewed BMJ Open study, with a 71% top-3 accuracy rate. Slothwise is an AI health assistant that connects to your actual medical records, wearables, and lab results to monitor your health continuously. Ada tells you what your symptoms might mean in one conversation. Slothwise knows your full health picture and watches for things that need attention over time. Slothwise is listed on Medicare.gov, one of only 13 apps selected. Ada is not.

What are Ada Health and Slothwise?

Ada Health is an AI-powered symptom assessment app founded in 2011 in Berlin. You describe your symptoms through a conversational Q&A, and the AI suggests possible conditions ranked by likelihood, along with guidance on what level of care to seek (self-care, see a doctor, go to the ER). Ada has raised over $200 million in funding, serves 13 to 14 million users, and has completed over 32 million symptom assessments. It is free for consumers. Revenue comes from enterprise contracts with health systems (Sutter Health), pharma companies (Novartis, Takeda), and insurers.

Slothwise is an AI health assistant that connects to your medical records from over 60,000 hospitals and clinics, syncs with 300+ wearable devices, and learns what is normal for you. It surfaces insights when something in your health data needs attention, explains lab results, checks medications against FDA safety alerts, tracks daily habits, and prepares doctor visit summaries. It is independently built with no external funding and is listed on the CMS Medicare App Library on Medicare.gov.

Think of Ada as a moment: "I feel something, what could it be?" Think of Slothwise as a relationship: "Here is your full health picture, and here is what has changed."

How do their features compare?

• AI symptom assessment: Ada's core strength. Its AI asks detailed follow-up questions about your symptoms and suggests possible conditions with likelihood rankings. Slothwise's AI answers health questions too, but grounded in your actual medical records and health history rather than symptoms described in a single conversation.

• Health records: Ada does not connect to your medical records, hospital data, or insurance portals. Slothwise connects to over 60,000 hospitals and clinics via Fasten Health, bringing your full medical history into one place.

• Wearable and device tracking: Ada does not integrate with wearables or health devices. Slothwise syncs with 300+ devices including Apple Health, Garmin, Oura, Whoop, and Fitbit.

• Lab result interpretation: Ada does not interpret lab results. Slothwise interprets 200+ lab markers with age- and sex-stratified reference ranges, explains what your results mean, and tracks trends over time.

• Ongoing monitoring: Ada provides a point-in-time assessment. Once you get your results, the interaction is over. Slothwise monitors your health data continuously and surfaces insights when something changes or needs attention.

• Daily health tracking: Ada does not offer tracking features. Slothwise tracks food (by photo, barcode, or voice), medications, hydration, weight, mood, blood pressure, blood glucose, and menstrual cycles.

• Doctor visit preparation: Ada generates a PDF summary of your symptom assessment that you can share with a doctor. Slothwise generates comprehensive doctor visit summaries by specialty, pulling from your full health record.

• Medical bill analysis: Ada does not analyze medical bills. Slothwise explains charges and identifies potential billing errors.

• Pricing: Ada is completely free for consumers. Slothwise has a free tier (50 messages, no credit card required) and a Pro subscription at $7.99/month for unlimited access.

• Text messaging access: Ada requires its app. Slothwise is accessible via text message with no app download required.

What does Ada Health do better?

Ada is the most clinically validated symptom checker available. It deserves genuine credit for its clinical evidence base, which is stronger than nearly any other consumer health AI.

• Diagnostic accuracy: A BMJ Open study found Ada placed the correct condition in its top 3 suggestions 71% of the time, compared to a 38% average across other symptom checkers tested. In a separate emergency department evaluation, Ada significantly outperformed ChatGPT 3.5 on triage safety, with an unsafe triage rate of 14% compared to 41% for ChatGPT.

• Care navigation impact: A 2026 study published in NEJM AI found that 38.5% of patients who planned an emergency department visit chose lower-acuity care after a single Ada assessment, and 93% of those redirections were clinically appropriate.

• Regulatory status: Ada is classified as a Class IIa medical device in the EU and holds ISO 27001 and ISO 13485 certifications. This is a meaningful level of regulatory oversight.

• Completely free: Ada's consumer product costs nothing. There is no paywall, no subscription, and no credit card required.

• Privacy: Ada does not sell user data. It is GDPR-compliant and ISO 27001 certified. This is a strong privacy posture.

What does Slothwise do better?

Ada answers a question: "What could this symptom be?" Slothwise answers a different one: "What is happening with my health, and what should I pay attention to?" These are fundamentally different tools.

The biggest difference is data. Ada does not know your medical history, your lab results, your medications, or your wearable data. It assesses the symptoms you describe in a single conversation. Slothwise connects to your actual records from hospitals, clinics, insurance portals, and wearable devices, and uses that data to surface insights, detect trends, and alert you when something needs attention.

Slothwise also goes beyond symptom checking into daily health management: tracking food and nutrition, monitoring medication schedules, analyzing medical bills, and preparing doctor visit summaries tailored to your upcoming appointment.

Slothwise is the only fully independent, patient-first AI health assistant listed on the CMS Medicare App Library on Medicare.gov, one of only 13 apps selected out of more than 350,000 health apps worldwide. It has earned the DiMe Seal for quality and trust in digital health. Ada holds neither credential.

Who should choose which?

• Choose Ada Health if you have a specific symptom right now and want to understand what it might mean before deciding whether to see a doctor. Ada is free, clinically validated, and good at what it does.

• Choose Slothwise if you want an AI health companion that connects to your medical records, monitors your health over time, explains your lab results, tracks your daily habits, and is independently verified on Medicare.gov.

• Use both: Ada and Slothwise complement each other well. Use Ada when you have a new symptom and want a quick assessment. Use Slothwise for everything else: understanding your records, tracking your health, preparing for doctor visits, and getting personalized insights based on your full health picture.

This article is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider for medical decisions.