"AI fitness app" covers three different things: apps that generate a workout from your history and equipment (Fitbod, Freeletics, Zing, FitnessAI), apps that run a program with rules and adjust the numbers (JuggernautAI, Alpha Progression), and coaches that also handle food and check in on you (Caliber with a human, Bay over text). Pick by which of those you want, not by the word "AI". The short answers: Fitbod or Zing for a generated gym session with no planning; Alpha Progression or JuggernautAI for a serious strength program with per-set recommendations; Bay if you want the plan, the progression, your meals and daily accountability in one place, free right now, without an app.
Prices are from each app's US App Store in-app purchase listing or its own website on November 4, 2026; they vary by platform, region and promotion.
The seven at a glance
| App | What the AI does | Food | Check-ins | Free tier | Price (checked Nov 2026) |
|---|---|---|---|---|---|
| Fitbod | Generates each session from your history, recovery and equipment | No | No | Trial only | $12.99–$15.99/mo; $79.99–$95.99/yr |
| Freeletics | Adaptive "Coach" plans for HIIT, bodyweight, weights and running | Separate Nutrition bundle | No | 34 bodyweight workouts | Training Coach $34.99–$79.99 by term; bundle $49.99–$89.99 |
| Zing | Plans from your data, daily energy/mood/sleep check, camera form feedback and body scan | No | Daily in-app | Trial | Premium $18.99–$59.99 by term; body scan $19.99 |
| FitnessAI | Sets, reps and weights generated per workout | No | No | Trial | $9.99–$19.99/mo; $59.99–$89.99/yr |
| JuggernautAI | Powerlifting and powerbuilding programs with daily, weekly and block adjustments from your readiness | No | No | Trial | $34.99/mo or $29.17/mo billed annually |
| Alpha Progression | Weight and rep recommendation for every working set; RIR-based | No | No | Full logging free | Pro $12.99/mo or $79.99/yr; 14-day trial |
| Bay | Builds a plan from your days, equipment and injuries; prescribes the weight per lift each morning; weekly calorie review | Yes: text, photo, voice | Daily, over text | Everything | Free right now |
Caliber is worth a mention outside the table: its free version generates workouts, and its paid tiers (Plus $6–$12 a month by term on the App Store) add tracking features; its premium offering is coaching by a human, which puts it in a different category.
The generated-session apps
Fitbod is the reference product: open the app, it has written today's session from what you did last time, which muscles are recovered and what equipment you told it you have. It is excellent at removing the planning step and weak at long-term progression on specific lifts, which is why people who get serious about strength tend to move on; see the Fitbod alternatives guide for that comparison.
Zing does the same for home and gym with more sensors: a daily check-in on energy, mood and sleep that adjusts the day's session, camera-based form feedback on supported movements, and a body-composition estimate from photos (sold separately on the App Store). Its subscriptions are listed by term from weekly to annual, so the effective monthly cost depends heavily on which you pick.
FitnessAI generates sets, reps and weights per workout from your log; it is the simplest of the three and priced across many terms.
Freeletics is the odd one out: its roots are bodyweight HIIT, and its Coach builds adaptive plans across HIIT, calisthenics, weights and running. The free tier is a fixed set of 34 bodyweight workouts. Nutrition is a separate coach sold in a bundle.
What they share: none logs your food, none texts you, and all require opening the app to train.
The program-with-rules apps
Alpha Progression tells you the weight and reps for every working set, built around reps in reserve, with deloads on Pro, and its free tier covers unlimited logging. It is the best choice for a hypertrophy-focused lifter who wants a next-set suggestion and already eats sensibly.
JuggernautAI is for powerlifters and powerbuilders: a periodised program adjusted daily, weekly and by block from your readiness, with meet-day attempt planning. It is the most expensive on the list, priced against human coaching rather than against apps.
The coach
Bay sits in the third category. It is not an app: you text it over iMessage, RCS or SMS. On training, you say "design me a plan" and it builds one from your goal, experience, days, minutes, equipment and anything that hurts, using the rules in how to build a personalized routine; each morning's text carries the session with the weight per lift, and progression is handled by rule (hit every rep, add the increment; miss twice, deload 10 percent), with a lighter fifth week once you are past the beginner stage. Then it does what the apps above do not: logs your meals from a sentence or a photo against verified label and chain-menu data, reviews your calorie targets every Sunday from your weight trend, and checks in once a day. It is free right now.
What Bay does not have: a live set-by-set screen with a rest timer, camera form feedback or a body scan. If you want to look at your phone between sets, pair it with a free logger such as Alpha Progression's free tier or Hevy or Strong.
How to choose
| You want | Pick |
|---|---|
| A gym session written for you, no planning | Fitbod or Zing |
| Home and bodyweight training with a plan | Freeletics or Zing |
| A next-set recommendation and RIR-based hypertrophy programming | Alpha Progression |
| A competitive powerlifting program | JuggernautAI |
| A plan, the weights to lift, your food and daily accountability, with nothing to install | Bay |
For a checklist to apply to any of them, see how to choose an AI personal trainer.
Questions, answered.
Tap a question.
What is the best AI fitness app?
It depends on the job. Fitbod and Zing generate sessions with no planning; Alpha Progression and JuggernautAI run rule-based strength programs; Bay is a coach over text that also handles food and check-ins and is free right now.
Are there free AI fitness apps?
Alpha Progression's free tier includes unlimited logging; Freeletics has 34 free bodyweight workouts; Caliber's free version generates workouts; Bay is free right now. Fitbod, Zing, FitnessAI and JuggernautAI offer trials, then subscriptions. The best free workout apps compares the free tiers in detail.
Do AI fitness apps track food?
Most do not. Freeletics sells a separate nutrition coach in a bundle; Bay logs meals from a text, photo or voice note and reviews your calorie targets weekly.
Is an AI fitness app as good as a personal trainer?
For programming, progression and consistency, the good ones do the job at a fraction of the cost; none can watch your form in the room the way a trainer can. The full comparison goes through the trade-offs.
Related reading
Bay is a software assistant, not a doctor, dietitian or certified trainer. Nothing here is medical, nutrition or professional advice; check with a professional before changing your diet or training.