NordicAim

What it does

NordicAim reads the paper target you just shot at 50 m and tells you what happened.

1. Photograph the target. Line up the live overlay with the black aiming mark, or import a photo you already took.
2. Say what you shot. Sight in, confirm, precision prone or precision standing, how many rounds, lighting. It takes a few seconds.
3. Read the analysis. Your phone finds the holes, lays the target over your photo, scores it, measures the group and builds one summary image you can share.

You always have the last word. Every hole and the alignment can be corrected by hand, and the score updates.

What you get

• Scores you can check. Precision targets score out of 100 with the X count and a ring tally. Sighting targets show hits and misses.
• Group size and point of impact. Extreme spread in millimetres and MOA, and the mean point of impact: how far, and which way, your group sits from centre. That is the number your sight adjustment starts from.
• One summary image. Sight in, confirm and the precision targets side by side, each drawn at the same scale so you can compare them by eye. Share it from the iPhone share sheet.
• Your rule, your call. Choose official gauge touch, centre in ring, or visible hole touch. Changing it re-scores every session you have stored, so old and new results stay comparable.
• Patterns over time. Every shot from every session, laid over the printed target for sight in, confirm, precision prone and precision standing. Show your latest session, your last 5 to 30, or all of them, for any season, and see whether your misses have a habit.
• Trends, session by session. The Analysis screen charts your score or hit rate, group size, accuracy (RMS distance from the centre) and point of impact with one point per session, and from three sessions draws a trend line on the score, group size and accuracy that says how much you are changing per session.
• A coach image. One picture of your recent sessions: the pattern drawings, then your averages in small boxes, each with an arrow showing which way it is trending, and a small bullseye showing where your average shot lands. Share it with your coach.
• Goals. Set where you want your prone and standing score, group size, accuracy and biathlon hits to be. Each chart draws the goal, says how the sessions since have done, and every session's results show whether it met the goals of its day.
• A Board, with no server. Your best 5 prone and standing targets of all time, signed and shared as a file, ranked against other shooters' files on your phone. Hand corrections are marked, and flagged when they move a score by more than 10 points. Add a small picture of yourself, or the Board shows your initials.
• Seasons. Narrow sessions, patterns, trends and goals to winter, spring, summer or fall.
• A review pass. Step through a session photo by photo, targets that need attention first.
• Backup and restore. One compressed file, named with your name and the date, holds all your sessions, and can be locked with your passphrase. Restore it on a new phone.

Two printed sheets are supported today: the sighting sheet and the Olympic 50 m rifle target used for precision work, shot with a .22 at 50 m.

The analysis engine

The score is only as good as the hole-finding behind it, so that is where the work went. Everything below runs on your phone, with no upload and no waiting on a server.

• Real computer vision, on the device. NordicAim ships OpenCV, the industry-standard vision library, running in the background so the screen never freezes. Your photos are analysed where they were taken.
• It measures the sheet, not just the photo. It finds the aiming mark, then measures every printed circle and the tilt of the paper, so the target is laid over your photo the way the sheet is actually hanging, not the way a template says it should.
• It reads the photo before it trusts it. A sharpness check, a guess at which sheet you photographed, and a lighting suggestion all come before a single hole is scored. If something is off, it tells you why.
• It finds holes on any background. Holes are found without assuming they are darker or lighter than the paper around them, and anywhere on the sheet, so a white ring, a black bull and a shadow are all fair game.
• It uses your backing colour. Photograph a card of your backing paper once and NordicAim learns the colour, so holes that show it stand out cleanly.
• Tuned on real targets. The detector was tuned and re-tuned against dozens of real photos of shot targets, with every hole marked by hand as the answer key, then reviewed by hand. Its misses and false alarms were counted, and the filters were reworked until the counts came down.
• Scored the way you choose. The same shots score under official gauge touch, centre in ring or visible hole touch, and every result says which rule it used.

It is not perfect, and it does not pretend to be. Suggested holes score nothing until you confirm them, and you can add, move or remove any shot. The engine does the tedious part, and you always have the last word.

For athletes and teams

Each athlete installs NordicAim on their own phone in about ten seconds. There is no account to create and nothing to set up for the squad.

Results move between athletes and coaches as summary images, and as coach images that sum up your recent sessions. Every image states which scoring rule was used and how many shots were found, so a coach reading it knows exactly what the numbers mean. If the squad compares scores, agree on one scoring rule in Settings first.

There is no shared team account or dashboard. Each phone keeps its own history.

Private, free, and light

• Everything happens on your phone. No server, no login, no analytics, no ads.
• Your photos stay yours. They are never uploaded, and NordicAim takes the location out of every photo as it is added. Only these can leave the phone, and only when you ask: the summary image or coach image you share, a Board file you share, and a backup file you create.
• Free to use. NordicAim is served as plain static files from GitHub Pages, so there is nothing to pay for and nothing to sign up to.
• Works at the range. After the first load it runs offline, so no signal is no problem.

Install on your iPhone

1. Open komplexmojo.github.io/NordicAim in Safari.
2. Tap Share, then Add to Home Screen.
3. Open NordicAim from your Home Screen.

The first load downloads the image analysis engine, so do it on Wi-Fi before you head to the range. There is no App Store and no Apple account involved.

Your sessions live on the phone. Deleting the Home Screen app deletes them, so use Settings, Back up now every so often and keep the file in Files or iCloud Drive. NordicAim reminds you when it has been a while.

Your first session

Something look off? Tap a target's picture on the results screen to add, move or remove a hole, or nudge the alignment. The score updates as you go.

Your brag sheet

When the session is done, NordicAim builds one summary image: your name and club if you set them in Settings, the session, the shooting and lighting conditions, every target with its score and group, and the session analysis. It is your brag sheet, and it is made to be shared. Tap Share and send it from the iPhone share sheet to your Strava or Garmin Connect activity as a photo, or to a coach or the squad chat.

You choose what to share and when. NordicAim does not connect to Strava or Garmin, and nothing is posted for you. The image leaves your phone only when you share it, and your photos never do.

Your trends, and one image for your coach

The Analysis screen, on the bottom bar beside Patterns, shows how you are moving with one point per session: score or hit rate, group size, accuracy and point of impact, with a dashed trend line from three sessions on the score, group size and accuracy.

Goals, and a board to compare with other shooters

Goals lets you set where you want your prone and standing score, group size, accuracy and biathlon hits to be, draws each goal on its chart, and says whether the sessions since have hit it. Each session's results and summary image show whether it met the goals you had at the time.

The Board ranks shooters by the average of their best 5 precision targets, one board for prone and one for standing. There is no server: you share your signed submission as a file and import other shooters', so each phone keeps its own board. Every target is scored again on the phone that receives it, targets corrected by hand are marked (and flagged when the correction moved the score more than 10 points). Anyone can open a target to see its automatic score beside a corrected one.

Sessions, Patterns, Analysis and Goals can each be narrowed to one season: winter, spring, summer or fall.

Want the whole routine, from installing to comparing against your history? See the workflow, step by step.

New to it? The guide covers getting good photos, reading the results, corrections, patterns, goals, the Board and backup in more detail.

Security and code review

NordicAim was built with Claude, and a cross-model security and code review has been performed on it: an independent review run in Cursor, by a different model from the one that wrote the code. Every finding is logged as a GitHub issue, so what was found, and what was done about it, is public. The privacy design is easy to check for yourself: no server, no runtime network calls, and a content security policy that enforces it.

Status and feedback

NordicAim is an early release, built in the open with biathletes who shoot. If a score looks wrong, a screen is confusing, or you want something it does not do, open an issue. A photo of the target helps, but check it carries no location you would rather keep private.

Licence and support

Using the app is free for everyone, including clubs, teams and coaches. The terms of use ask only that you don't sell it or bundle it into something paid, don't host or copy it elsewhere, and leave the KomplexMojo credit on summary images.

The source code is published so you can see how it works, under the PolyForm Strict License 1.0.0: you may read and run it for noncommercial use, but not modify or redistribute it, and code contributions are not accepted (why). It is source-available, not open source. The "NordicAim" name and logo are not licensed for reuse. Third-party components keep their own licences (NOTICE.md).

NordicAim is built in response to what its users ask for. If it earns a place in your training, supporting its development is the best way to shape what comes next.

Developed using NordicAim by KomplexMojo. Every summary image carries that credit.

About the project

NordicAim is a Vite and React web app that runs entirely in the browser on the phone, with no backend. The analysis pipeline (OpenCV in a Web Worker), scoring and rendering are all client-side and covered by unit and end-to-end tests.

• Requires Node 22 and pnpm 10 (corepack enable picks up the pinned packageManager version).

pnpm install
pnpm dev          # http://127.0.0.1:3874
pnpm dev:test     # same, with VITE_FAKE_CAMERA=1 (used by Playwright)
pnpm build        # tsc -b && vite build
pnpm preview      # http://127.0.0.1:4173

pnpm check        # typecheck + lint + unit tests + privacy check (the gate for every milestone)
pnpm typecheck
pnpm lint
pnpm test         # Vitest unit tests
pnpm test:e2e     # Playwright, mobile Chromium + mobile WebKit
pnpm test:e2e:offline  # Playwright against the production build, offline after the first load
pnpm check:privacy
pnpm make:icons   # regenerate public/icons/* (sharp; concentric-ring motif)
pnpm docs:screens -- --hero-only  # rebuild docs/assets/hero-screens.png from the phone screenshots in docs/assets/screens/
pnpm docs:screens # preview only: replaces those real screenshots with demo-data ones from the fake-camera build

Pushing to main deploys to GitHub Pages (.github/workflows/pages.yml). To run the capability checks on an iPhone, open https://komplexmojo.github.io/NordicAim/#/diagnostics in Safari and again after Add to Home Screen, since some checks (storage persistence, share) behave differently as a standalone app.

Documentation map

Doc	What it is
docs/guide/	The user guide
docs/brand/	Brand kit: logo, palette, voice, app icons
docs/DESIGN.md	Original product design (verbatim)
docs/DESIGN-REVISIONS.md	Owner decisions that define the MVP and supersede parts of the design
docs/BACKLOG.md	Post-MVP items (not to be built without go-ahead)
docs/PLAN.md	Plan: verified facts, decisions, corrections, risks, open questions
docs/spec/	Source-of-truth specs: analysis pipeline, geometry and scoring, data model and storage, capture overlay, metadata and lighting, diagrams and summary image, patterns, analysis and the coach image, backup and restore, provenance, privacy, storage and hosting
docs/milestones/	MVP milestones sized for lower-reasoning agents
AGENTS.md	Rules for any agent implementing a milestone

Out of scope

Apple Health, Strava and multi-user accounts.

Privacy of this repository

There is no server: all data stays on the phone. This repository is public and contains code only. The original target photos contain GPS and live only in the gitignored fixtures/private/. pnpm check:privacy fails if any tracked image carries GPS EXIF.