What Pip can and cannot measure.

Four-angle photo method

Pip asks for front, left, back, and right standing photographs. On iPhone, Apple Vision and device motion help check framing, pose, outline, and phone stillness during capture. The photos are then used for AI body analysis and to create a textured 3D exterior body model.

Photographs do not see internal tissue. Clothing, posture, camera height, lighting, hydration, recent meals, and training can materially change appearance. Repeat scans are most useful when those conditions are similar.

AI body analysis

After the user agrees, Pip prepares background-removed, head-masked copies of the four photos and sends them with limited body context to OpenAI through Pip's Railway service. The model returns a bounded set of exterior shape observations, plausible body-fat bands, and regional evidence. Pip validates the response before using it.

The request tells the model not to infer identity, race, ethnicity, diagnosis, health status, pregnancy, medication use, treatment response, strength, performance, or athleticism from the photos. The result may still be wrong and is not a diagnosis or direct measurement.

Textured 3D body

After the user agrees, Pip separately sends the four full photos through its Railway service to Meshy, which creates a textured exterior 3D model of the body that the user can turn and zoom. Meshy's copy is deleted once the body is saved on the iPhone. Separately, the iPhone fits its own body model on the device for the measurements and outlines.

A 3D body is a visual representation, not a scan of internal anatomy. It can smooth, miss, or exaggerate body shape and should be compared only with other Pip check-ins captured under similar conditions.

Displayed body-fat and waist estimates

Pip may show an estimated body-fat range, an estimated waist value, and an estimated fat-free mass range. Body-fat is presented as a range because the photo evidence does not support a precise percentage. Waist is inferred from the fitted exterior model and entered height; it is not a tape-measure reading. Fat-free mass is not muscle mass, and Pip does not estimate visceral fat, metabolic age, or BMI.

Pip has not completed an independent criterion study against DXA, a four-component body-composition assessment, or technician tape measures. Individual error, subgroup performance, repeatability, and sensitivity to real change are therefore not established. Do not treat these values as clinical measurements.

Ask Pip answer method

Ask Pip answers questions about the user's own saved record on the device. When the user separately agrees to AI answers, Pip sends the question and only the relevant details needed to answer it to OpenAI. Answers about medicines link to sources found by live web search, limited to an approved list that includes regulators, the NHS, NICE, NIH, ClinicalTrials.gov, PubMed, major journals, and manufacturers. General wellness answers may have no sources.

Ask Pip may explain general label or trial doses as education, but it gives no personal dosing advice. It will not choose a dose or titration step, help buy, source, mix, or prepare research peptides, or diagnose. Urgent symptoms receive a fixed answer pointing to emergency services. Ask Pip is an education and record-reflection tool, not a medical-advice service.

What published research supports

Research shows that purpose-built photo or 3D optical models can estimate body composition when trained and validated against a criterion method. Examples include a smartphone-photo validation study and external validation of 3D optical imaging. These studies support the field's feasibility; they do not validate Pip or transfer their accuracy to Pip.

• Majmudar et al.: smartphone camera adiposity validation against DXA
• Harty et al.: machine learning and 3D optical imaging
• Cerqueira et al.: systematic review of Body Adiposity Index validity

Safe interpretation

• Treat every shape and number as an uncertain AI estimate.
• Compare check-ins only when capture conditions are similar.
• Do not infer diagnosis, health status, or treatment effect.
• Use a qualified clinician and appropriate reference method for health decisions.

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