fi8

The fast way to train smarter

Voice-first · Body composition · Smart routines · Coach access
🎙 Voice logging 🔥 Training streak 🥇 Recent bests 🫁 Coverage map 📊 Body scans 👔 Coach access 📱 PWA, no app store
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Sign in with Google. fi8 shows everything it does before you commit. Your dashboard fills in from the moment you log your first set.

Sign-in screen
Everything fi8 does, visible before you sign up
fi8
The fast way to train smarter
🎙
Voice logging
Hands-free, instant
⏱
Rest timer
Auto-starts after sets
📈
Progression
+2.5 kg suggestions
📊
Body scans
Composition analytics
Continue with Google
🏢 Via your gym
Dashboard
Body scan stats, weekly sessions. Tap the ⓘ on Bio Age, BMR, or Visceral for a plain-English definition
fi8
Say it. Track it. Improve it.
J
Good morning, James
Sunday, June 29
84.2kg
Weight
38.1kg
Muscle
18.3%
Body Fat
32
Bio Age i
1840
BMR i
6
Visceral i
This week · 3 sessions
TODAYPush A52 min
FRIPull B48 min
WEDBack & Core44 min

🎙 Voice-first workout logging

Just tap the mic and say your exercise. No menus. When it mishears, retry in one tap, or switch to manual with the transcript pre-filled.

Session in progress
Voice logged, rest timer counting down automatically
fi8
Say it. Track it. Improve it.
J
Push A · Jun 29
18:42
3 exercises logged
Rest
1:12
skip
✓ Bench Press · Set 2 → 80kg × 10
Bench Press
80kg × 10 80kg × 10
Squat
100kg × 8 102.5kg × 7
Voice error recovery
Mishear? Retry in one tap or pre-fill manual entry
fi8
Say it. Track it. Improve it.
J
SUN · Jun 29
12:04
1 exercise logged
Couldn't understand that
Heard: "bench press 100 killers 8 reps"
Try saying:
100 kilos 100 kg
⌨ Type it
🎙 Try again
Squat
100kg × 8
Guided routines
Mode labels clearly explain the difference between guided and free
fi8
Say it. Track it. Improve it.
J
Guided routines
MON
🎯 Guided
Push & High
7 exercises · targets, rest timer, progression
WED
🎯 Guided
Pull & Front
6 exercises · targets, rest timer, progression
🎤 Free session
No plan. Log whatever you're doing by voice. Great for flexible days.
+ Start Free Session

🎯 Guided sessions + progressive overload

fi8 tells you which exercise is next, tracks your targets in real time, then suggests a weight increase after every session where you hit your goals.

Pre-session edit
Tap any exercise to adjust Sets, Reps, or kg before you start
Push & High
Tap any exercise to adjust targets for today
Bench Press
4 sets · 8 reps · 80 kg
tap to adjust ›
✕
Squat
5 sets · 5 reps · 100 kg
✕
Sets
5
Reps
5
kg
100
OHP
4 sets · 8 reps · 50 kg
tap to adjust ›
✕
Start Session
Session summary
Stats + progressive overload suggestion shown after every session
fi8
J
🎉
Session Complete!
Push & High · 52 min
4
Exercises
16
Sets
5.2t
Volume
Next session targets
Bench Press Try 82.5 kg ↑
Squat Try 102.5 kg ↑
Done

📈 Progress & history Rebuilt

Rebuilt so the tab opens on evidence rather than warnings: a training streak, the bests you set recently, and every lift labelled where it stands. Below that, a coverage map of what is going untrained, fat and lean mass drawn to one scale, and a filterable history with set-level drill-down.

Streak, recent bests & lift status New
Opens on what you have done, not what you are missing. Every lift says where it stands in words, with its own trend line
fi8
J
Progress
14
14 weeks without
missing one.
105 sessions · 13 in 30 days
Recent bests
8 in 45 days
🥇
Chest Press
175 lb × 6
Yesterday
🥈
Squat (Smith)
230 lb × 5
3 days ago
🥉
Your lifts
Deadlift
315 lb × 4
At your best
Bench Press (DB)
175 lb × 3
New best
Squat (Smith)
230 lb × 5
New best
Coverage map & body recomposition New
What you are missing as a picture, not a sentence. Fat and lean mass drawn to one scale so a recomposition is visible at a glance
fi8
J
Coverage · last 4 weeks
Covered chest, quads, glutes Light back, arms Nothing shoulders, calves, core
Body composition
Oct 202591.4 kg
24
67.4 kg lean
Aug 202683.4 kg
15.6
67.8 kg lean
−8.4kg
Fat mass
+0.4kg
Lean mass
−7.5pts
Body fat
History with filter & drill-down
Search by exercise, filter by chip, expand any session for set-level detail
fi8
J
History
🔍 Search exercises…
Bench Press
Squat
Deadlift
3 sessions
Push & High · Jun 29
4 exercises · 16 sets
52 min▶
Bench Press
Set 180 kg × 10
Set 280 kg × 10
Set 382.5 kg × 8
Pull & Front · Jun 27
5 exercises · 18 sets
48 min▶

👔 Built for coaches too

Coaches manage members, log sessions on their behalf, and add body scan data. Members see their coach's name and can remove access any time.

Coach view
Distinct initials, real last-session dates, request button below the list
fi8
Sign Out
Say it. Track it. Improve it.
Select Trainee
Choose whose dashboard to view
🖥️
My Training (you)
Your own workouts
›
JA
James Anderson
Last session: Jun 29
›
AK
Ahmed Khan
No sessions yet
›
+ Request New Trainee
Coach in profile
Members see their assigned coach, remove or change anytime
fi8
J
J
James Anderson
Coach Access
Your Coach
Samia Hussain
Remove
Change
Add Scan
Short, clear button text, works with any body scan device, not just one brand
fi8
J
Add Scan
DATE
Jun 29, 2026
WEIGHT (KG)
84.2
BODY FAT %
18.3
MUSCLE (KG)
38.1
Save
Cancel

✨ AI-written progress notes

A real sentence, written by Claude, after every session and body-scan import — tying the numbers together in plain English instead of just showing totals.

Session Summary
Written fresh after every session, not a canned template
🎉
Session Complete!
52 min · Leg Day
4,120 kg
VOLUME
14
SETS
52 min
DURATION
✨ WRITTEN BY AI
Strong leg day — your squat working weight is up 8% over the last month and every set landed in your target rep range. Try +2.5 kg next time.
Body Scan Digest
Segmental arm/leg/torso lean+fat breakdown, read against your history
fi8
J
Progress
Segmental breakdown
Arms
Legs
Torso
LeanFat
✨ WRITTEN BY AI
Since your last scan you've gained 0.4 kg of lean mass while dropping 1.1 kg of fat — a clean recomposition month. Visceral fat is back in the healthy range too.

🗂 Admin Console Updated

A dedicated desktop console for the gym owner, built for a laptop rather than squeezed into a phone, and now with a route straight back to the member app. Opens on a dashboard: who is active, sessions logged over 14 days, how the coaching load is spread, and who has not trained in a fortnight. Everything is scoped to your own gym by security rules, not by a filter, and regular members never see it at all. It works on a phone too.

Gym Admin console Updated
Opens on a dashboard, not a list: engagement KPIs, a 14-day session chart, coach load, and who is about to lapse — all scoped to your gym only
fi8.app/console
Dashboard
Iron Peak Fitness · Gym Admin
👤 Alex · Gym Admin ← App Sign out
Active Members
42/ 47
Sessions This Week
118
Coach : Trainee
1 : 12
Churn Risk
3members
Sessions logged, last 14 days 118 this week
Coach load trainees
JA
James Anderson
Coach: Samia Hussain
Sep 4Active
AK
Ahmed Khan
No coach assigned
Aug 7Inactive 28d

Cleaner nav, smarter access Updated

Your gym's own branding in the header. A "View as" bar for anyone holding more than one role, so a coach who also trains, or an admin who does both, moves between them in one tap. Gym card in the bottom nav. Display name set by members, seen by coaches.

Switch role in one tap New
One account can hold gym admin, coach and trainee at once. A "View as" bar appears only when more than one is held
fi8
YourGym
J
View as Trainee Coach Admin
Good evening, James
Friday, September 5
Next up
Push & High
4 exercises · 16 sets
This week
Gym card tab
One tap from anywhere, no digging through menus
fi8
Say it. Track it. Improve it.
J
Your Gym Card
Scan at reception
4829 1047 3821
James Anderson
Member since Jan 2026
Display name
Set your name once, coaches see it instantly, not your Gmail username
fi8
J
J
James Anderson
Display Name
James Anderson
Shown to your coach instead of your Google username
Save Name

Everything in fi8

A complete toolkit for members and coaches who take training seriously.

🔥
Training streak New
Consecutive weeks with at least one session, with a 26-week bar strip. The current week never breaks the run while it is still empty.
🥇
Recent bests New
Every all-time best set in the last 45 days, medal-ranked with its own trend line. A single uncorroborated set that jumps too far is not treated as a record.
🏷
Lift status badges New
New best, at your best, holding or paused. Repeating a hard lift is no longer reported as a failure just because the number has not moved.
🫁
Coverage map New
Front and back body map shaded by how many direct sets each muscle group got in the last 4 weeks. What is going untrained, without reading a sentence.
⚖️
Recomposition bars New
First and latest body scan as fat and lean mass on one shared scale, so losing fat while holding muscle is visible rather than inferred from two lines.
📊
Volume blocks New
Total load moved per 4-week block, in your own unit, with the change on the previous block.
🔀
Role switcher New
Hold gym admin, coach and trainee on one account and move between them in one tap. Hidden entirely unless you hold more than one.
🏛
Your gym's branding New
Your gym's logo sits beside fi8 in the header, at a size that actually reads on a phone.
🎙
Voice Logging
Say "bench press 80 kg 10 reps" and the app logs it instantly. Supports kg, lbs, and duration.
⏱
Auto Rest Timer
90-second countdown starts automatically after every logged set. Beep + vibration when time's up.
📈
Progressive Overload
After a session where you hit all targets, fi8 suggests +2.5 kg for next time, shown in the post-session summary.
🎉
Session Summary
Total volume, sets, duration, and progression tips shown after every session before returning to the dashboard.
✏️
Pre-session editing
Tap any exercise before starting to adjust Sets, Reps, or kg for that session, without changing the routine permanently.
🔍
History drill-down
Search by exercise name, filter by chip, and expand any session to see each individual set: weight and reps per set.
☰
Hamburger menu
Top nav decluttered. Profile, Tour, Bug Report, and Admin actions live in a clean dropdown. Admin-only items are highlighted.
💳
Gym card in nav
Gym card moved to the bottom nav as a dedicated tab, one tap from anywhere in the app, always visible.
👤
Member display name
Set your name once in your profile. Coaches always see your chosen name, not your Google account username.
🗂
Admin Console
Admin now opens its own dedicated desktop console in a new tab, with Members, Coaches, Invites, Requests, and Bug Reports tabs, plus real KPIs and charts scoped to your gym.
✨
AI-written progress notes
A real sentence, written by Claude, after every session and body-scan import — tying the numbers together in plain English instead of just showing totals.
ⓘ
Jargon tooltips
Tap the ⓘ next to Bio Age, BMR, or Visceral on the Dashboard for a one-line, plain-English explanation, no guessing at fitness jargon.
🏋️
Clearer trainee list
Coaches see two-letter initials (no more mixing up trainees who share a first initial) and each trainee's actual last-session date, not a static label.
📊
Body Scan Tracking
Log weight, body fat %, lean mass, bio age, BMR, visceral fat after each scan, plus a segmental arm/leg/torso breakdown, from any body scan device.
🔁
Custom Routines
Build push/pull/legs routines and follow them with guided prompts, targets, and real-time rest timer.
🏆
Personal Records
Best weight×reps per exercise, with a sparkline trend and estimated 1RM, rated against strength standards (Beginner → Elite).
👔
Coach Dashboard
Coaches switch between members, log on their behalf, and add scan data. Members can revoke access any time.
📱
PWA · Any Device
Fully responsive progressive web app. Works on phone, tablet, or desktop. Install from the browser, no app store.
🏢
Available Through Your Gym
fi8 is gym-membership software, not a public app — there's no open signup. Your gym's admin sends you an invite link (7-day expiry) to set up your trainee or coach account.

Data & Security

Your members' data, handled the way you'd want it handled.

fi8 has no public sign-up. Every trainee and coach account exists because your gym invited them, and the moment your gym cancels, your data doesn't get folded into some shared pool: it stays yours, isolated from every other gym on fi8, and you can export all of it before you go. Nothing about how fi8 handles your members' data is left to guesswork.

Sign-in runs through Google, which means fi8 never asks for, sees, or stores a password. Coach access to a trainee's workouts and body composition scans only happens after the trainee explicitly grants it from their own profile, and they can revoke it in one tap, any time, no questions asked. Your gym's coaches see your members' data. Other gyms never do.

fi8 runs on Google Cloud infrastructure through Firebase, the same backend platform trusted by companies well beyond fitness. We don't sell member data, we don't hand it to advertisers, and we don't use it to train anything outside of fi8 itself. If billing questions come up: Stripe handles payment details directly once billing goes live, and fi8 never touches a raw card number.

One thing worth being upfront about: fi8 is a wellness tracking tool, not a medical device. The body composition numbers and "bio age" estimate your members see are wellness estimates meant to show trends over time, not clinical or diagnostic results. We built fi8 to help your members train smarter, not to replace a doctor.

Want your full data exported, or a plain answer to a specific question about how we handle something? Ask us directly, we'll give you a straight answer, not a runaround.

Read the full Privacy Policy and Terms of Service for all the details.

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