Reference
Seasonal atlases by species
Cross-reactivity and seasonal timing data are organized by species rather than a single blended pollen count, matching how allergists actually reason about triggers.
Depth over a single daily number.
WEB / IOS / ANDROID
PollenMap
Seasonal pollen atlases, cross-reactivity, and a personal symptom diary for allergy sufferers.
Try it liveExpoReact NativeTypeScriptCloudflare Workers
AT A GLANCE
Offline-First
Architecture
Species-Level
Atlases
Private
Symptom Diary
Optional
Push Alerts
THE PROBLEM
Pollen allergy tools are either too generic or too invasive
General pollen-count apps rarely go past a single city-wide number, while more capable allergy-tracking tools often require handing over health data to a server by default. Allergy sufferers needed real reference depth without an automatic privacy trade-off.
HOW IT WAS BUILT
Offline-first by default, opt-in for anything live
PollenMap is an Expo and React Native app built around seasonal pollen atlases, cross-reactivity lookups, and a private, on-device symptom diary that works fully without any backend.
An optional Cloudflare Worker adds a live pollen forecast and opt-in push alerts for users who want them, but the reference and tracking core of the app never requires it.
INSIDE THE PRODUCT
Core surfaces that define the experience
Tracking
A symptom diary that stays private
Diary entries, severity ratings, and sIgE values are stored on-device by default, so tracking a season of symptoms doesn’t require trusting a server with health data.
Privacy is the default, not a setting to find.
Alerts
Live forecasts stay opt-in
A Cloudflare Worker backend adds live pollen forecasts and push alerts for users who want them, sharing only region and sensitized species — never the full diary.
The app works completely without ever opting in.
KEY FEATURES
What makes it work
Seasonal Atlases, Not a Live Map
PollenMap’s "map" is species-level seasonal atlases and cross-reactivity data, not a live GIS pollen-count layer — a deliberate choice for reference accuracy over real-time novelty.
On-Device Symptom Diary
Personal data — diary entries, notes, severity ratings, sIgE values — stays on the device by default; only opting into push alerts shares a region and sensitized-species list with the backend.
Clinician-Facing Modules
Beyond personal tracking, dedicated modules present the same data in a form suited to sharing patterns with a doctor or allergist.
WORKFLOW
How a season gets tracked
PollenMap is built around a season-long loop of reference, logging, and — optionally — live alerts.
01
Look up species-level seasonal data
Seasonal atlases and cross-reactivity lookups give a starting picture of what’s likely triggering symptoms during a given window.
02
Log symptoms privately, on-device
Diary entries and severity ratings accumulate locally, building a personal record without any data leaving the device by default.
03
Opt into live forecasts if useful
Users who want real-time pollen forecasts and push alerts can opt in, sharing only what’s needed for that feature and nothing more.