Supertrainer is in Open testing! We need testers!

The best drill in your library is useless if half your squad is on the bench

It's 8:40 on a Saturday morning and the texts start arriving. One player's hamstring is "still tight from Thursday." Another slept badly all week and their parent is keeping them home. A third rolled an ankle at practice you ran two days before a match, doing a full-intensity shooting drill because that's what was written on the plan.

If you coach youth sports, you know this morning. You planned for eleven and you're warming up seven.

Here's the uncomfortable part: a lot of those absences trace back to us, the coaches. Not because we don't care, but because we plan practices on a clipboard from memory. We can't see that this week's training load is double what a kid's body has been used to over the past month. We don't know that a player has been sleeping badly and dragging for four straight sessions, because nobody asked. So we run the hard session anyway, and on Saturday the roster is thin.

Professional clubs solved this years ago with sports scientists, GPS vests, and wellness questionnaires. A volunteer coach with a day job gets none of that. That gap is why I built Super Trainer.

What it is

Super Trainer is a practice-planning app for grassroots coaches that treats player availability as a first-class problem. It runs on Android tablets and phones today, with iOS in TestFlight. Everything works offline, on the sideline, with no signal and no account. Your data lives on your device. If you just want to give it a try, download it from the play store now.

The familiar coaching tools are all there. A drill library with about fifty drills you can filter by intensity, category, or tag, plus your own custom ones:

Drill library on a tablet, list on the left, full setup and instructions on the right

A practice plan builder where you sequence drills, set minutes per slot, and watch the total update:

A saved U12 practice plan, warm-up through cooldown, 79 minutes total

And a formation board where you drag players from your roster onto the pitch, with separate in-possession and out-of-possession shapes:

Formation screen, pick a preset, drag players from the squad list onto the pitch

The part that answers the Saturday-morning texts

The health side is where Super Trainer stops being a digital clipboard.

Before practice, while players are still arriving, you walk the roster and log four quick ratings per player: sleep, soreness, fatigue, mood. It takes three or four minutes. Each player's name gets a color: green is ready to train, amber means keep an eye on them, red means back off their load today. A red badge isn't a weak kid. It's information you didn't have before.

The pre-practice wellness check-in — four quick ratings per player, done while the squad is still arriving

After practice, you ask each player one question: "one to ten, how hard was that?" The app multiplies their answer by the session length and that becomes their training load for the day. Over the weeks, it compares each player's current load to their rolling four-week average — a ratio sports scientists call ACWR. When this week's load spikes far above what a player's body has adapted to, injury risk climbs. The dashboard shows who's in the safe band and who's drifting out of it, so you find out before the hamstring does.

Logging RPE after a session, one tap per player, and the app does the load math

The scheduling side feeds into this too. Put your matches in the calendar and the auto-planner adjusts on its own: full sessions when the next game is four or more days out, lighter work at two days, recovery only the day before. You can override anything, but the default stops you from accidentally running beep tests on a Friday night.

The game schedule, the auto-planner reads those "in 5 days" badges and tapers training to match

When someone does get hurt, there's an injury log that tracks body area, severity, and recovery status, and counts their missed sessions automatically. No more trying to remember whether a player has been out for two weeks or four. Mostly, though, the injury tab is a screen I want coaches to see in exactly one state:

The injury tab, the way every coach wants to find it: no active injuries, all players cleared to train

Built for the sideline, not the office

A few decisions I held onto stubbornly while building this:

Offline first. Practice happens on fields with bad reception. Every feature works with airplane mode on; sync across devices exists but it's optional and it waits until you have signal.

One codebase, every pocket. The app is written in Rust with the Slint UI toolkit, and the same code ships to Android and iOS, tablet and phone. A drill detail that reads well on a 10-inch tablet also has to survive a 5-inch phone screen held in one hand at the edge of the pitch:

The same drill detail on a phone, full setup and instructions, one thumb

No accounts, no data harvesting. You're logging children's wellness data. That belongs on your device, not on my server, unless you deliberately turn on sync for backup.

Where it stands

Super Trainer is in open testing on Google Play right now and I need testers. anyone can install it and try it today. The iOS build is in TestFlight working toward App Store release. It's been shaped heavily by one very patient beta coach who tells me exactly which screens make sense on the field and which ones were clearly designed by a programmer at a desk.

Open testing means exactly what it sounds like: the app is finished enough to run your season with, and I want more coaches banging on it before the full release. If something confuses you or breaks, there's a feedback button built right into the app (the ? at the top), and I read every submission.....but for real, I actually do.

If you coach, any sport, soccer at any level, but especially if you're the volunteer parent running two sessions a week, I'd genuinely like to hear how you handle this today. What do you track? What do you wish you knew before a kid limps off?

And if your Saturday mornings sound like mine used to, the roster might be trying to tell you something a clipboard can't.

Super Trainer is built by MNK Solutions. Android: open testing on Google Play. iOS: TestFlight, App Store soon.