🩸 Blood, highlighted
The camera view goes grey; blood stays in colour and the phone buzzes when a drop is inside the circle.
🍁 Calibrate out red leaves
One tap on nearby ground with no blood teaches the app what red is already there — sumac, maple, berries — so it stops lighting them up.
👁️ Colorblind-safe
Show blood in blue or yellow instead of red. Built for the one in twelve men who can't tell red from brown.
📍 Pin every find
Tap Mark at first blood, every drop, the pools and last blood. Each pin keeps a photo and its GPS position.
🧭 Back to last blood
Lost the trail? A compass arrow and distance lead you back to your last find. Works with no cell signal — GPS doesn't need one.
🔦 Day or night
Turn on the phone's torch from the scanner. Strict, Normal and Wide settings for red-leaf ground or old, dark blood.
Choose a colour you can actually see
Private by design
The camera picture is processed on your iPhone and never recorded or uploaded. Your trails, pins and photos stay on your phone. No account, no ads, no analytics.
Pricing
Free: five minutes of scanning a day and one saved trail — and your pins, the trail map and Back to last blood are always free, even when the minutes run out. Blood Trail Pro adds unlimited scanning, unlimited trails, GPX export for a partner or tracking-dog handler, and checking photos from your library — $4.99 a month or $19.99 a year with a 7-day free trial.