An iPhone app from the Rack
Log it. Time it. Lift each other up. A lifting log that brings your history, talks you through rest, and stays out of your way.
Free during the beta · Keep the app you use now · Your whole log exports any time
Coming from Hevy or Strong
Bring it
All of it comes over.
Export from Hevy (Settings, Export & Import Data) or Strong (Settings, Export Data) and open the file in IronStack, or bring any spreadsheet you kept. Sessions, routines as workouts, supersets paired the way you paired them, prep sets and drop sets tagged as what they were. Names it knows are matched; names it does not are kept exactly as you had them. A preview shows what it found before anything is saved.
Keep your app
Nothing here needs you to quit.
The import reads a file you exported. It never signs in to Hevy or Strong, never touches your account, and bringing the same file twice adds nothing. Run both for a couple of weeks and keep whichever earns it.
Tap, type or say it
You never have to talk to it.
Last time's weight and reps are already in every set, so most sets are one tap to confirm. Or type 225x8 in the one field. Voice is there for the days your hands are covered in chalk, and only while you hold the button.
JuggernautAI history comes over the same way. What it will not do yet: a watch app, Android, or exercise videos. If you need those, keep the other app for them.
What it does differently
Every screen here is the real app on my phone, with my own training behind it. Social is the app's sample feed, because my spotters' sessions are theirs to share, not mine.
Logging · Chalk on your hands
Tap it, type it, or say it.
Last time's numbers are already in the set: tap to confirm. Changed something? Type 225x8 @7 in the one field. Or hold the talk button and say "two twenty five for eight at seven"; "same again" and "switch to hack squat" work too. Speech is turned into text on the phone, offline, and only while you hold the button.
Other apps: Tap the numbers in, set by set, with a keypad.
The clock · Chalk on your hands
A rest clock you can read from the platform.
The set lands and rest starts itself, at the length the program asked for. With earbuds in, a recorded voice calls "Thirty seconds", "Five seconds" and "Get to work", and your music dips under it and comes back. Voice, buzz or off, and it minds the silent switch. On screen the last ten seconds go oxblood and the last three fill the top and beat. On the Lock Screen, "same again" logs another set like the last without unlocking the phone.
Other apps: A timer that buzzes, and a phone to unlock to log the next set.
Plan · Capture cannot fail
Bring the plan you already have.
Programs, workouts and exercises, on one tab. Bring your history over from Hevy, Strong, JuggernautAI or any spreadsheet you kept, send Coach a photo or PDF of your program and it writes it down, or save today's session as a workout. Workouts hold your targets, 3 × 8 · 135 lb, and next time last session's numbers are already in every set. Logging becomes confirming.
Other apps: Routines and custom exercises capped on the free tier.
Insights · You against you
Every number is you against you.
Sessions this month against last, your estimated max over twelve weeks, records by name, a progress line on every exercise, and how you lift on the days you feel good against the flat ones. Measured against your own log and nobody else's. When the data is thin, it says so instead of guessing.
Other apps: Graphs, only the last three months of them on Hevy's free tier. Working out what they mean is your job.
Social · Lift each other up
A quiet way to share with the people you train with.
Invite a training partner by text. Share a session as a card: time, sets, the best thing you did. No strangers, and no comments, on purpose: the one thing to give is support, and you see who gave it. If your crew lives in the comments, this is not trying to replace that. Social is optional, and nothing else here needs it.
Other apps: Followers, strangers, likes and comments.
Coach · You against you
A coach with a ceiling.
Ask what to open at, what covers a taken rack, or how today went. Send it a photo or PDF of the program your coach wrote and it writes it down for you to check. Every weight it names comes from your own sets, under a ceiling it can show you, with the set the ceiling came from. Nothing it suggests lands in your log until you tap. Not a doctor, and it says so.
Other apps: A chatbot that invents a number, or no number at all.
Screens from IronStack 0.1.1 in the iPhone Simulator, loaded with my own training log, Sept 29, 2026. Coach is from my iPhone. The Social screen is the sample feed the app shows before you sign in.
Why it exists
The first IronStack lived on my laptop, and it was good at telling me what a week meant. Then one day I named an exercise it had never heard of, and it would not take the set. A log that can refuse a set you did is not a log.
So I rebuilt it around one rule, and put it on my phone, because the rack is where the set happens and my hands are covered in chalk. I wanted a log that takes whatever you did, reads the clock to you, and treats the people you train with as partners rather than an audience. Four ideas hold up everything it does.
Try it
Voice is optional; typing the same words works too. These are the examples on the app's own voice card. Tap one to see what it writes down. Then start a rest and watch the end of it.
You say
IronStack writes
225x8 @7
225 lb for 8 reps at RPE 7, on the lift you are doing.
Rest
0:20
Twenty seconds here; three minutes in the gym. Watch the last ten.
Speech becomes text on the phone, offline, and only while you hold the button. Weight comes before reps, the way lifters say it; RPE is how hard it was on a scale to 10, and the app explains it wherever you rate a set. The rest clock is the length your program asked for. The app never records what you actually rested, because it does not know.
How you use it
Coming from Hevy, Strong, JuggernautAI or a spreadsheet? Export, open the file, and the preview says what it found before anything lands: sessions, workouts, and names to check. Or skip it and log your first set. That starts the session.
Tap the number that is already there, type it, or say it. Rest starts itself. Bodyweight comes from Apple Health if you let it, and you can always type over it. Tap the weight to change it; the keypad converts pounds and kilos on the spot.
Finish and the session closes on what mattered: time, working sets, records by name, a badge if you earned one. Share the card with your spotters, or don't. Next time, today's lifts are waiting with what you hit.
An exercise is not always a lift: the collection covers barbell, machines and bodybuilding, conditioning (twenty minutes on the air bike is a session too) and strongman, browsable by muscle group. Every exercise has a load card that fits it: a loaded bar with plate math, a fixed bar, a stack, bodyweight or a band. Plate math switches itself off for cables, machines, dumbbells, kettlebells and bands. Home or Away on Today for sessions on the road, flipped by hand or automatically when you are far from home, and shared with MealStack if it is on the phone. A Home Screen widget, and badges that grow with you over years, not just the first week. Apple Health fills in your weigh-in, and can take each session as a strength workout. Your whole log exports in one file, in a documented format, any time.
Side by side
Written against Hevy's and Strong's free tiers as of September 2026. If a line is wrong, tell me and it changes.
The fine print, in plain words
The code
Closed app. Open data.
IronStack is a closed-source app from Mission Built. What is open is your data: everything you log exports in one file in the Mission Built Schema, a documented, versioned format, and imports back in. The IronStack name and the marks stay with Mission Built.
Price
Not settled yet. Here is why.
Every Coach question runs on a server I pay for. I want Coach in the app and I am not willing to lose money keeping it there, so the launch price is open: free with Coach on an allowance, a one-time price, or Coach as the paid part of a free app. What is settled: logging, the clock, your whole history and Social will not be what you pay for.
Your data
On your phone. Yours to take.
Your log is files on your phone, and one tap exports all of it in the Mission Built Schema, a documented, versioned format. Coach and Social send only what they need to work. One screen deletes everything, everywhere, and tells you what it deleted. The privacy page says exactly what, where and for how long.
Not a doctor. Not your programmer.
I am not a coach or a clinician, and nothing on this page or in the app is advice about how you should train. IronStack is how I log my own. Coach is an AI: it gives a starting weight under a ceiling it can show you, a cue from your own notes, or an alternative when the rack is taken. It writes down the program you send it and never makes one up, and any question about pain or injury gets pointed to a qualified person.
Join the beta
Newest build: IronStack 0.1.1 · Build 50
IronStack logs every session I do, and a small group of outside testers is on it with me. New testers come in small batches, added by hand from the email on your Apple ID, and I would especially like people coming from Hevy or Strong, and training partners who want to try Social together.
You get an email from TestFlight, Apple's own app for trying apps before they reach the App Store: install TestFlight, tap the link, and IronStack installs like any other app. Keep Hevy or Strong on your phone the whole time. The address is used for the invite and nothing else.
Training with someone? Sign up together and put their name in the note, and I will add you in the same batch.
The form is not taking names right now. Email [email protected] with the address on your Apple ID and I will add you by hand.
By invite, from the form. Small batches, added by hand.
The public door, published by Mission Built.
Questions
At the table
The phone is where the set gets written down. What you do with the record after that is up to you: it leaves the app as plain files, in a published format, whenever you ask, and any tool you like can read them.
An append-only file per day, one event per set, that the app writes and nothing rewrites. Corrections are new lines, never edits. Export the raw log in Settings hands it over as it is, one line per event.
Export all my data writes one file in the Mission Built Schema: every session and set, your programs, workouts and exercises, and your units. Map coordinates only if you switch them on. Anything that reads JSON reads it, and Bring in data takes it back on a new phone.
A spreadsheet, a script, a notebook, a database, or the dashboards you already run. I index mine into Elasticsearch and read it in Kibana: how heavy a week was, whether I am ramping, what I have been neglecting. That is a choice, not a requirement; the file works the same in whatever you use.
For testers
Terms of use (a draft, under review) · Privacy · Support · Acknowledgements
Also from Mission Built
Log it · Time it · Lift each other up
Stacked.