The Fly Box field guide & inventory

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Sort

Tell it what the river's doing and it ranks your box. Any picker left blank is ignored. Flies that produced on logged trips get a boost.

Fly type
Season
Time of day
Weather
Water speed
Water temp (°F, optional)
35°off75°
River

My rivers

Waters you fish. Rivers show up as a filter in On the Water, in the trip form, and in trip history.

Your data

Backup & restore

One file with everything on this device — inventory, notes, photos, rivers, trips. Save one after every good outing.

Import inventory

Replace your inventory from a CSV. Three formats work: one row per pattern (Fly Pattern, Type, Qty, Size(s)), one row per size (Fly Pattern, Type, Size, Qty), or this app\u2019s own exports. Library patterns auto-populate all field-guide info.

Trip history

Export your trips as a spreadsheet (one row per fly, trip details repeated), or import trips from a CSV in that format or from a Fly Box backup file. Imports merge with what's here — exact duplicates are skipped.

Export

The inventory export includes every field-guide column, filled in where the library knows the pattern — the complete format for building a fly box from scratch. Fill in the blanks (or start from the empty template) and import it right back; new patterns with their columns filled become part of this device's pattern library.

Install on your phone

iPhone: open this page in Safari → Share → Add to Home Screen. Android: Chrome menu → Add to Home screen. After the first visit it works fully offline, like an app. Share the web address with fishing buddies — their inventory and trips stay on their own phones.

Data mode

Each switch is a clean wipe of everything on this device — inventory, trips, notes, photos. Download a backup first if anything here matters.

FAQ — tips from the field

Does it work with no cell service?
Yes — that's the whole point. Open it once with internet and after that everything works offline: the field guide, the matcher, trip logging, even GPS capture (the GPS chip doesn't need signal, just sky). Only updates and the map links need a connection.
How do I put it on my phone like a real app?
iPhone: open the web address in Safari → Share → Add to Home Screen. Android: Chrome menu → Add to Home screen. It gets an icon and launches full-screen.
How do updates work? Do I need to refresh or clear anything?
Just open the app when you have signal — new versions load automatically. If the app was already open during an update, close it and reopen. Never clear Safari's cache or website data to force an update — that can erase your flies and trips. Updates themselves never touch your data.
Is my data online? Who can see my spots?
Nobody. The web address serves the app, not your data. Your inventory, trips, notes, GPS points and photos are stored only on this device and never leave it.
How does it know it's me and not a buddy I shared it with?
It doesn't need to — each phone keeps its own completely separate data. Share the web address freely; friends start with their own fresh box and can never see or change yours.
How do I move everything to a new phone?
On the old phone: More → Download full backup. Send that file to the new phone (AirDrop, email), then More → Restore from backup. Everything comes across: flies, trips, notes, photos, rivers.
My flies or trips vanished — what happened?
Two usual suspects: you opened the app somewhere else (Safari, Chrome, and the home-screen icon each keep separate data — stick to one), or the phone cleared website storage. Either way the fix is the same: More → Restore from your latest backup. Which is why backups after good trips are the habit worth having.
What does "Unsorted" mean under a fly's sizes?
Flies counted before per-size tracking, or added without a size. As you sort your physical box, move them over: tap − on Unsorted and + on the real size.
What do the marks in On the Water mean?
★ worked on your logged trips · ★★ produced in similar conditions or on the picked river · ✎ recommended for that river · ☆ a fishing partner reported success · ✗ no luck on past trips (sinks it down the list) · 📍 produced near where you're standing.
Why does a missed fish count in a fly's favor?
A fish that rose to your fly means the pattern choice was right, even if the hookset wasn't. Only "No luck" counts against a fly.
What's the fastest way to log a trip on the water?
Trips → Quick log, tap the mic button on the keyboard, and just talk: date, river, conditions, what worked, what didn't, what your buddy caught. The app fills out the trip form from your words — review it and save.
What if I add a fly the app doesn't know?
It's flagged "needs library info" and still fully usable. To give it field-guide knowledge: More → Export inventory CSV, fill in that fly's columns in any spreadsheet, and import it back — it becomes part of this device's library, matcher and all.
Can my buddy's catches mess up my inventory?
No. Partner catches logged on trips inform future recommendations only — they never change your fly counts.
Photos won't save or the app says storage is full?
Photos are by far the biggest use of the app's device storage. If saving fails, remove photos from a few patterns you don't need pictured. Your photos are included in backups, so nothing has to be lost.
Two anglers sharing one phone?
One device means one shared box — separate profiles aren't supported (yet). A second device, or a backup/restore swap ritual, is the workaround.

Pattern library: patterns of fishing knowledge, bundled in this file. Share the file itself — each person's inventory, notes and trips stay on their own device.