Comparison

Stretch Strong vs CheckIn Pro

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Stretch Strong

Access a vast library of over 400 stretching exercises with video demonstrations and expert-led weekly workouts. Find specific stretches for your sport or needs with powerful search and filtering tools. Track your progress with an in-app journal.

Highlights
  • 400+ stretching exercises with video demonstrations
  • Expert-led weekly flexibility workouts
  • Search, filter, and substitute functions
  • Novice and experienced training tracks
  • In-app training journal
  • Tutorial videos and FAQ resource library
Features
Read full description

Unlock Your Ultimate Flexibility with Stretch Strong! Over 400+ stretching exercises and growing! With search, filtering, and substitution functions, you'll be able to explore a world of flexibility training you can't find anywhere else online! With Jon Call (@jujimufu), a flexibility expert with over 20 years of experience competing in Martial Arts, Bodybuilding, and Strength Sports, you'll get new weekly flexibility workouts created by him (that he does himself!) that you can incorporate into your training. The weekly workouts are quick and effective, demanding only 1 hour per week of total work to see improvements for even the busiest or biggest athletes out there! There are two versions of the weekly workouts: a novice version and an experienced version that you can jump between. Most flexibility apps out there are AI abominations with no link to reality or real people. Stretch Strong demystifies flexibility training and has busy people and actual athletes in mind. We make flexibility convenient but also specific. Just search the database for stretches related to your sport or need and try them out! Stretch Strong has features that help make it incredibly easy for you to continue stretching with a multitude of customizations. With the Stretch Strong app, you can: – Explore explanations and in-app video demonstrations for every movement in our exercise library of 400+ movements, many of which you've never seen anywhere else! – Navigate the exercise library with filter, substitute, and search functions to find the stretch you need when you need it quickly! – Stay updated with weekly videos and notes with the exact flexibility training focus of any given week, as well as the broader context of where we are in a flexibility training cycle. – Learn with our extensive Tutorial Video and FAQ resource library to help you understand flexibility training principles, techniques, and considerations that can affect your stretching. – Get a new week of flexibility programming every Sunday with two training tracks: Novice and Experienced. – Use an in-app training journal with references to recent performance to track your results. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

CheckIn Pro

Features
Read full description

CheckIn Pro is the check‑in camera built for physique athletes — bodybuilding, classic physique, men's physique, bikini, figure, wellness, and anyone tracking their transformation. Tired of setting timers and running back into frame, only to get inconsistent results? CheckIn Pro takes the hassle out of your weekly check-in and makes it a smooth, repeatable process. Pose-guided, hands-free capture and ghost-overlay alignment mean every shot lines up — so your check-ins stay consistent and you have time to hit the pose just right. CheckIn Pro tracks every pose and how many weeks out you are from your show, keeping your whole prep organized. CAPTURE THE RIGHT WAY • Guided sessions walk you through your division's mandatory poses • Hands‑free: start each pose by voice ("let's go" — or your own catch phrase), motion‑stillness, or a timer • Ghost overlay of your last shot so you match framing every time • Burst Mode takes multiple shots of each pose (optional) SEE YOUR PROGRESS • Side‑by‑side and blended overlay comparisons • Auto‑align two photos; isolate yourself onto a clean background (on‑device) • Export timelapse animations to show your prep over time TRACK THE NUMBERS • Log weight and measurements; see trends and weekly change • Goal countdown with prep progress • Multi‑show career: organize check‑ins by show and compare across years PRIVACY FIRST: YOUR DATA STAYS YOURS • 100% on-device — your check-ins are never uploaded to our servers • No account, no sign-up. Back up or export only when you choose to. • Coached? Send a whole session straight to your coach — email it or drop it in any shared cloud folder. Stop guessing whether you're improving. Check in, line it up, and dominate. CHECKIN PRO PREMIUM Your library is always free to view and compare. Premium unlocks unlimited check‑ins, exports, photo import, background removal, and multiple shows. CheckIn Pro Premium is an auto‑renewing subscription: Monthly $2.99 or Annual $24.99. Payment is charged to your Apple Account at confirmation of purchase. The subscription renews automatically unless cancelled at least 24 hours before the end of the current period. Manage or cancel anytime in your Apple Account settings. Privacy Policy: https://checkinpro.gamifiedapps.com/privacy/ Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Stretch Strong4 screens
CheckIn Pro4 screens

Verdict

The call

The clearest difference is update cadence: CheckIn Pro at every 2 days against Stretch Strong's every 3 months. On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Stretch Strong sells 3 in-app purchases, starting at $8.99 per month and CheckIn Pro sells 2 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Stretch Strong ships an update every 3 months, CheckIn Pro every 2 days. The most recent releases landed on July 5, 2026 and September 19, 2026 respectively.

Scorecard1 real difference · 9 level
Stretch Strong versus CheckIn Pro: the parameters behind the verdict, then further details
ParameterStretch StrongCheckIn Pro
PriceFreeFree
Rating4.4 (62 ratings) — better—
Positive reviews66.7% of reviews—
Number of ratings62 — better—
Update frequencyEvery 3 monthsEvery 2 days — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS15.1 — better15.5
Further details — not scored
Size139 MB83 MB
Age rating17+4+
DeveloperTrainmakr LLCSteve Yu

In-app purchases

3 purchases

Stretch Strong

Subscriptions3
  • Monthly7 Days trial$8.991 Month
  • Quarterly7 Days trial$25.003 Months
  • Yearly7 Days trial$89.991 Year
2 purchases

CheckIn Pro

Subscriptions2
  • CheckIn Pro Monthly$2.991 Month
  • CheckIn Pro Annual Subscription$24.991 Year

Questions

Is Stretch Strong free?
Stretch Strong is free to download, with in-app purchases available.
Is CheckIn Pro free?
CheckIn Pro is free to download, with in-app purchases available.
Do Stretch Strong or CheckIn Pro have ads?
Neither Stretch Strong nor CheckIn Pro shows ads.
Which is updated more often, Stretch Strong or CheckIn Pro?
Stretch Strong ships an update every 3 months, and CheckIn Pro every 2 days. Most recently, Stretch Strong was updated on July 5, 2026 and CheckIn Pro on September 19, 2026.

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