We built the AI beauty app over 14 weeks: (1) AI skin analysis: the user takes a selfie and an on-device computer vision model (trained on 500,000 annotated skin images with dermatologist validation) analyzes skin type (oily, dry, combination, sensitive), skin concerns (fine lines, dark spots, redness, texture, acne), skin tone (Fitzpatrick scale plus undertone), and visible skin age. All analysis runs on-device — selfie images are never uploaded. The model was trained with diverse skin tones and types, validated by dermatologists for bias and accuracy. (2) Personalized routine builder: based on the AI skin analysis and a lifestyle questionnaire (climate, sun exposure, sleep, stress, diet), the app generates a personalized skincare routine using the brand's products — morning and evening routines with product recommendations, usage instructions, and expected results timeline.
The recommendation engine understands product interactions (which serums layer well, which actives should not be combined) and builds routines from the brand's product range, not generic ingredient lists. (3) Virtual try-on: AR-powered makeup try-on using ARKit (iOS) and ARCore (Android) with AI color-matching — the user sees lipstick, eyeshadow, and foundation colors rendered on their face in real-time, with AI adjusting for lighting conditions, skin tone, and texture. The AI ensures that color rendering is accurate across skin tones — a critical requirement for a luxury brand. (4) AI beauty advisor: an in-app conversational AI (powered by Mistral for French, GPT-4o for other languages) that answers beauty questions, explains ingredients, provides application tips, and adapts recommendations based on seasonal changes and user feedback. The advisor communicates in the brand's voice — sophisticated, knowledgeable, and never pushy. French users interact in French with culturally appropriate formality.
(5) CNIL compliance: on-device skin analysis (selfies never leave the phone), AIPD completed, transparent AI explanation ("your routine is recommended because your skin analysis shows combination skin with dehydration concerns"), and CNIL-compliant consent for personalization data.