Forensika
When circumstances aren't clear, forensic science brings light and precision. Tools and apps for forensic medicine and toxicology.
What forensic science is
Forensic science links law and the natural sciences. In place of assumption it brings measurement, a defined method and verifiable evidence: in criminal cases, traffic collisions, and in establishing the cause of death.
It is made up of several disciplines, each answering a different question.
Forensic medicine & toxicology
Establishes the cause and mechanism of death, assesses injuries and how they arose, and proves the presence of drugs, medication or poisons in the body.
Forensic genetics & biology
Uses blood, saliva, hair with roots and other biological traces to establish identity and link a specific person to a scene.
Fingerprint analysis
Compares finger and palm prints: one of the oldest identification methods, and still among the most reliable.
Ballistics
Examines firearms, ammunition and gunshot residue, making it possible to determine direction, distance and sequence of fire.
Digital forensics
Recovers and preserves data from computers, phones and storage media, including traces someone tried to erase.
Forensic chemistry & physics
Identifies unknown substances, paints, glass, fibres and microtraces: often the very evidence that connects the unconnected.
None of these disciplines stands alone: they say the most when their findings come together in a single case, which is why sharing knowledge, aligning methods and cooperating across institutions matters.
Forensic apps in your pocket
Tools for the autopsy table, the scene, and for writing protocols and reports. Built from a forensic pathologist's own practice; they work offline and cite the source of every method.
4n6 Tools
Calculators and reference tables for forensic medicine, for use at the autopsy table, at the scene and when writing protocols and expert reports. They cover Henssge time-of-death estimation from rectal temperature (Marshall–Hoare) with a correction-factor selector and 95 % confidence intervals, PMI from rigor mortis and lividity, vitreous K⁺, the Traub index, ethanol interpretation and calculations (Widmark, back-calculation), toxicology reference concentrations across therapeutic – toxic – lethal ranges, BMI and nutritional status, body surface area and expected heart weight, age from aortic circumferences, stature and age from bone lengths, skeletal sex and age, forensic entomology and a unit converter.
Version 5.5 adds Polish, Hungarian, Chinese (Simplified), Spanish and Portuguese (Brazil), so the app now speaks twelve languages, results and report included; Lite 5.3 does too. Version 5.4 brings three appearance themes (Laboratory instrument, Coloured glass and Black and gold, each in light and dark), a home-screen card for the active case and a correction of the Henssge calculation in warm environments (from 23.3 °C). Version 5.3 adds Czech, German, Italian, French and Ukrainian, so the app now speaks seven languages, results and report included. Version 5.2 was rebuilt from the ground up: a new design, a revision of the methods against the original literature and new tools: DVI per the INTERPOL DVI Guide 2023, burns (Lund–Browder, Baux), CO-Hb with vitality assessment, reference levels for 67 substances including post-mortem femoral blood values, and Case & Report with a shared export and case backup. Available on the App Store and Google Play. Since version 5.1, Lite also opens the other tools as a preview: the form, the method and the references; Pro calculates the result.
Every tool states the published method it rests on, and its citation. Everything runs on device, with no account and no data leaving the phone.
Colorime3ka
Measures and names the colour of a skin finding from a photograph or the live camera. What decides is not the colour itself but the chromophore behind it: melanin darkens the whole area and holds a yellow-brown hue, haemoglobin adds colour yet barely darkens, dried blood has a very dark red-brown core, and a scar is recognised by what it lacks. The robust colour of the area is converted to CIELAB and named by ΔE (CIEDE2000), alongside uniformity, sharpness of the margin, surface roughness, outline and the hue gradient from centre to edge.
Calibration with a grey card and a 24-patch colour chart makes series comparable; a millimetre scale comes from two taps on a ruler, or on iPhone Pro straight from LiDAR, with no ruler. Two assessment modes: forensic (bruises, abrasions, wounds, crusts and scars, erythema, vitality and dating) and dermatological (pigmented lesions and melanoma by ABCDE, efflorescences, inflammatory and vascular changes). Atlas of 68 findings with original schematic drawings. Version 3.1 added the body region to the clinical context and grading of postoperative wound healing on the Southampton score: pus and wound dehiscence are not assessed from a photograph. Version 3.2 made aiming more precise: a point dragged under the loupe stays exactly where you lift your finger, and scale points can be moved afterwards with a finger or Apple Pencil. Version 3.3 is fully available in German, and the atlas has ten new drawings showing the surface and a cross-section.
Percentages express the agreement of measured features with reference criteria, not diagnostic certainty: the upper limit is 85 %. The app does not date a bruise, and states this explicitly: colour tables assigning a number of days have not held up in more recent work, and the only indication supported by the literature is the yellow component, which is not seen in a bruise younger than roughly 18 hours. A 12-page professional manual ships in Slovak, English and German.
littlEye AI
Teach your own model to recognise histology slides directly on an iPhone, iPad or Mac: with no internet and without a single pixel leaving the device. The H&E dataset spans 27 organs and tissues; slides are reviewed by colleagues with an audit trail, and the final diagnosis is settled by majority vote. Core ML training runs on device and always reports an independent test set, a confusion matrix, and sensitivity and precision per class: students see where a model fails, not just where it succeeds.
Staining is recorded (H&E, PAS, trichrome, silver, elastic and more) and magnifications run from 4× to 1000×; learning from corrections returns a misread slide to the dataset. .le3AI models and .le3set datasets are encrypted and carry their own metrics and audit trail. An atlas of over 100 diagnoses and an education module: special stains, IHC markers, cellular elements and pigments: every entry with a source citation. Case workflow: scanner slides attached to a case number, a tissue check that flags a possible slide mix-up, and a concise summary of findings to the clipboard. Developed with three institutes of the Faculty of Medicine, Comenius University in Bratislava.
The app is a tool, not a collection of models: it ships with a single demonstration model trained on synthetic patterns. Real models are trained from your own slides or exchanged with colleagues as standalone .le3AI files; they never were and never will be part of the app. The licence-clean colorectal carcinoma model (NCT-CRC dataset, CC BY 4.0) distinguishes 9 tumour components and reaches 88 % on 7,180 images from fifty patients it has never seen; it is available free on request. Versions 3.2–3.3 added image quantification, a desmin IHC calculator and tools for publication (image quality control, threshold sensitivity, ICC and Bland–Altman). Version 4.0 brought a new look and clearer navigation that follows the workflow, from import to training and sharing; .le3AI and .le3set files remain compatible with version 3.x. Since version 3.0 the app is free: the voluntary in-app contribution unlocks nothing.
aPrehliadky
A photogrammetric 3D scanner for bodies and objects. Capture with LiDAR gives every frame depth and gravity and a metric camera trajectory from which the app derives the model scale; without LiDAR, the ARKit trajectory and a calibration target supply the scale. Reconstruction runs entirely on device through RealityKit Object Capture: classical photogrammetry, with no NeRF, no Gaussian splatting and no AI-completed geometry. The model is built only from captured data, and the report states this explicitly.
You can measure distance, a path along the surface that follows uneven and curved shapes (wound length, circumference), area and volume; a polyline sums straight segments (body length with flexed limbs). A reference of known length verifies the scale of the whole model, a fit to the LiDAR trajectory provides an independent check, and every measurement carries an uncertainty ± U (k = 2). Findings are marked with numbered pins, and the surroundings can be captured as a second metric model of the room: the position of a body in a space is a finding in itself. The output is a PDF report, a 3D documentation certificate of class A–D based on how many independent routes substantiate the scale, and an .f3d package with a SHA-256 of every file; on import, the recipient sees whether it was modified. The professional Fotograme3ka 3D companion for Mac (Apple Silicon, €34.99 one-time) recomputes the package at higher detail, even from an older iPhone without LiDAR, and handles examination, measurement and the report on a large screen. Version 3.2 added pausing a capture, position recovery after an interruption and a consistency check of the scale sources; Fotograme3ka 2.1 has computation presets (Forensic: 300k triangles, 8K texture) and a computation record inside the package and the report.
Designed as a possible add-on to ePrehliadky (the software of the Slovak Health Care Surveillance Authority, ÚDZS): an independent app by the author, not a product of ÚDZS. It is not a certified measuring instrument; accuracy depends on capture conditions and should be verified with a reference of known length.
Congressa
A folded paper programme in a jacket pocket, leafing between days and looking for the hall of my own talk: that is why Congressa exists. Load the conference programme once (straight from the conference website, from a PDF, from the organiser's server or from a colleague's QR code) and it keeps working offline, even where a congress hall has no signal. The Now screen shows what is on, what comes next and where to go; in My plan you star the talks you care about and the app reminds you a few minutes ahead and warns about clashes. If you present or chair, your slots are highlighted and reminded first.
When the organiser runs a Congressa server, you also get sign-up for dinners, trips and workshops with capacity and a waiting list, and announcements straight to the phone. The programme is shared by QR code: a colleague has it in seconds, on iPhone or Android; anyone without the app is sent to the right store and the same programme loads by itself after installing. The app is available in thirteen languages (SK, CZ, EN, DE, FR, ES, IT, UA, PL, HU, ZH, JA, KO). My conferences keeps an archive of attended events and issues a PDF certificate of attendance. No account, no ads, no tracking.
An independent app by the author: not made by the conference organiser. Free and complete; an optional in-app tip supports development and unlocks nothing.
Independent research, funded by the author and the users
Forensika has no ads, no investors and no subscriptions, and it sells no data. Development and the research behind the apps (method validation, accuracy tests, validation studies) are so far funded by the author himself, alongside his work as a forensic pathologist. 4n6 Tools Lite, aPrehliadky, littlEye AI and Congressa remain free for everyone. The costs are helped by one-time purchases of the professional tools: 4n6 Tools Pro, Colorime3ka and Fotograme3ka 3D for Mac, the optional aPrehliadky Pro licence for institutions that want packages and reports cryptographically signed, and voluntary in-app contributions.
Every purchase means updates for new iOS and macOS releases, new tools, method revisions and answers straight from the author. If the apps help you in your practice, buying them is the best way to make sure they carry on. Thank you.
All of these are research and support tools for qualified professionals: they are not medical devices and do not provide a diagnosis. They support professional judgement rather than replacing it: the final assessment always belongs to the forensic physician or pathologist.
4n6 Pro + Colorime3ka + 3D
Three apps by the same author in one package: calculations at the autopsy table, objective colour measurement of findings and a 3D model from photographs on the Mac.
4n6 Tools ProiOS
27 professional tools: time of death (Henssge nomogram, post-mortem changes, vitreous potassium, entomology), toxicology, burns, identification and DVI. Offline, with the source of every method.
Colorime3kaiOS
Measures the colour of a skin finding from a photograph, names the nearest reference colour and shows the chromophore behind it.
Fotograme3ka 3DMac
Turns the aPrehliadky photo package into a 3D model on your Mac and sends it back to your iPhone. No cloud, requires an Apple Silicon Mac with macOS 15.
Separately: 4n6 Tools Pro €104.99 · Colorime3ka €17.99 · Fotograme3ka 3D €34.99.
Black Friday Nov 23-30, 2026: 4n6 Tools Pro €89.99 (usually €104.99) · Colorime3ka €14.99 (usually €17.99) · Fotograme3ka 3D €29.99 (usually €34.99). The bundle stays at €119.99.
The bundle is available on the App Store only. If you already own one of the apps, the App Store counts what you have paid. Prices on the Slovak App Store, they may vary by country. The tools support professional judgement and do not replace it.
The methods behind the apps
Overviews for forensic pathologists and students: how a method works, where its limits are and which literature it rests on.
Estimating time of death from rectal temperature: the Henssge nomogram in practice
How the Henssge nomogram works, how to choose the corrective factor, how wide the 95 % interval is and when the result does not hold. An overview for forensic pathologists and students.
Bruise colour from a photograph: what can be measured and what cannot
How to document the colour of a bruise, abrasion or scar objectively: CIELAB, ΔE (CIEDE2000), grey-card calibration, and why the age of a bruise cannot be determined reliably from its colour.
3D documentation of an examination with an iPhone: scale, uncertainty and integrity
How photographs and LiDAR become a measurable 3D model of a body or a scene, how the scale is verified, what an uncertainty of ± U (k = 2) means, documentation classes A to D and SHA-256 integrity.
The last objective witness
Forensic medicine objectively establishes the cause and mechanism of death, contributes to justice, and protects public health, where uncertainty remains, it brings verifiable evidence and clarity.