Pick Strong if you already know what you are going to lift and want the fastest, cleanest way to record it. Pick JEFIT if you want the app to build a plan and suggest weights and reps for you, and you check first which parts of that are free. The details below come from each app's own App Store listing and website, checked on 20 September 2026, so you can see where the real differences are before you commit your training history to either one.

The short version

• Strong is a logger. Its listing describes recording workouts, routines, personal records, one-rep-max estimates and graphs, and it makes no claim to choose your next weight.

• JEFIT is a logger plus a planner. Its listing describes an adaptive plan and an AI-powered progressive overload system that suggests what weight and reps to lift next.

• Both have Apple Watch support, body measurement tracking and a rest timer, and both are free to download.

Strong: fast, quiet and built for a routine you already have

Strong describes itself as the simplest and most intuitive workout tracker and says it is optimised for a progressive barbell routine such as Starting Strength or StrongLifts 5x5. That is an accurate picture of the app: you build routines, log sets, and let the app show your history, personal bests and estimated one-rep max. It has a warm-up calculator and a plate calculator, supersets, set tags for warm-up, drop and failure sets, a Live Activity for rest timers, and CSV export of your data.

The free version saves unlimited workouts but limits you to three custom routines. Strong Pro costs $4.99 a month or $29.99 a year in the US and removes that limit and adds further features. At the time of checking, the listing carried a 4.9 average rating from roughly 108,000 ratings, and the app supports ten languages, including Japanese, Korean, Portuguese and Russian.

What Strong does not do, by its own description, is tell you what to put on the bar next. That is a design choice, and for lifters who follow a written programme it is often the right one.

JEFIT: a bigger toolbox, with the planning behind a paywall

JEFIT covers more ground. Its listing cites a library of more than 1,400 exercises with video instructions, built-in bodybuilding programmes, supersets, set tags, muscle-focus and weekly-sets charts, an estimated one-rep max, a muscle recovery chart, body measurements and Apple Watch sync. It also describes an Adaptive Plan, built around your goal, level and equipment, that adapts every week, and a progressive overload system that analyses your past logs to suggest weight and reps. A recent update note says adaptive plans now pause weight progressions during deload weeks.

Two things are worth checking before you pay. First, the listing places the adaptive AI coach under JEFIT Elite, which costs $12.99 a month or $69.99 a year in the US, but it also lists the progressive overload system among its core features. It does not make clear which parts you get on the free tier, so test it in the app first. Second, the listing describes what the system does, not the rule it follows, so when it suggests a weight you cannot see why. Whether that matters depends on how much you want to understand your own progression.

JEFIT's listing shows a 4.8 average rating from roughly 47,000 ratings, and offers English, French, German, Italian, Chinese and Spanish, which is fewer languages than Strong.

What the difference looks like at the bar

Take a bench press with a target of 3 sets of 8 to 12 reps. Last session you did 12, 12 and 12 at 60 kg (132 lb).

• In Strong, the history shows those 12s, and you decide what comes next. Most lifters would add the smallest plate jump, but the choice is yours and the app does not push back either way.

• In JEFIT, the suggestion comes from its adaptive system. You may get a small increase or a different set and rep scheme, and you cannot inspect the reasoning.

• The third option, a fixed and visible rule, is what our own explainer on double progression describes: top of the range on every set earns a small increase, anything less repeats the weight.

Neither of the first two is wrong. The question is whether you want to make that call, hand it to a system, or hand it to a rule you can read.

Which to choose

• Choose Strong if you follow a programme, want the least friction while you train, want a full Apple Watch app, or want to stay cheap: the free tier is generous for anyone with three routines or fewer.

• Choose JEFIT if you want an exercise library with video, an app that builds and adapts a plan for you, and muscle-level analytics, and you have checked which of the adaptive parts you get without paying.

• Consider a third option if what you want is neither a blank logger nor an opaque plan, but a clear next-weight target for each lift. Alpha Progression is the paid-coach option, and we compare it in Alpha Progression vs Hevy.

Where Adensa fits

Adensa is an iPhone app that prescribes the next weight and rep target for each lift, and it publishes the rules it uses in Settings under “How we calculate”. If you hit the top of your rep range on every set, the load rises by 5% on a compound lift or 2.5% on an isolation lift, rounded to your plate step with a minimum of one step. In the bench press example above, 60 kg becomes 62.5 kg (138 lb). If you fall short, it holds the weight and asks for more reps, and after repeated misses on the same lift it takes 10% off that lift.

Before a workout you choose Recover, Steady or Push, and after it you rate the session's effort from 1 to 10. A tough session with missed targets makes the app suggest Recover next time. All of that coaching is free. Adensa Pro adds history beyond 30 days, the reasoning behind each insight, per-exercise progression tuning, the recap archive and iCloud sync.

The trade-offs are real. Adensa is iPhone only and has no Apple Watch app, and it does not generate a training plan for you. It also imports workout history from Strong and Hevy, but not from JEFIT, so switching from JEFIT would mean starting the history fresh.

If you are on Strong and curious what a next-weight prescription would look like on your own numbers, you can import your Strong CSV into Adensa and compare it against what you would have chosen: see how Adensa works.