Comparison

Struix vs MergeHDR

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

Head to head
About

Struix

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Your camera has the sensor. Your iPhone has the processor. Struix brings computational photography — the multi-frame merging phones do automatically — to the RAW files from your real camera, entirely on device. Import a shoot over Wi-Fi, from an SD card, or your Photos library. Struix automatically finds the bracket and burst sets in it and merges each one the right way, in a single tap — no lining up frames by hand, no desktop. WHY IT'S DIFFERENT • Automatic. It detects your exposure brackets and bursts and picks the right merge for each — you don't sort, pair, or select anything. • More than HDR. Bursts merge into a cleaner, lower-noise frame; exposure brackets merge into wider dynamic range. One tool for both, not just tone-mapped HDR. • A real computational pipeline. A raw-domain, multi-frame merge — the class of technique behind modern phone cameras — not a filter or a simple blend. • Standard DNG out. Every result is a tiled DNG that opens in Lightroom, Pixelmator, and other RAW editors, ready to finish. TUNED FOR YOUR CAMERA Deeply tuned for OM SYSTEM and Olympus — detection, color, and rendering are calibrated to the bodies enthusiasts actually shoot. It also imports and merges RAW from many other cameras via your Photos library or an SD card. MADE FOR THE MOMENT Everything runs on your iPhone — no cloud, no account, no cables, no computer. Merge on the train right after the shoot. FREE • Import, browse, and convert RAW to DNG — unlimited • Your first 10 computational merges — free, no time limit STRUIX PRO — unlimited merges • Lifetime: a one-time $29.99, yours forever • Or subscribe: $14.99/year or $4.99/month, each with a 7-day free trial Subscriptions are charged to your Apple Account and auto-renew unless cancelled at least 24 hours before the period ends; manage or cancel anytime in Settings. The lifetime option is a one-time purchase with no renewal. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://teamstruix.github.io/privacy.html PRIVACY Struix processes every photo on device. No accounts, no tracking, no data collection. Your images never leave your iPhone unless you export them. OM SYSTEM and Olympus are trademarks of their respective owners. Struix is an independent app and is not affiliated with, endorsed by, or sponsored by those companies.

About

MergeHDR

Automatically finds and merges exposure-bracketed photos from your library. Offers manual control over alignment, deghosting, and tone-mapping for professional HDR results. All processing happens on your device for privacy and offline use.

Highlights
  • Automatic exposure bracket detection
  • Manual alignment and deghosting
  • Adjustable tone-mapping styles
  • Per-exposure layer control
  • On-device processing
  • Export to HEIC
  • Universal Purchase
Features
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Your camera already shot the brackets. MergeHDR finds them. Point a camera at a sunset and a single exposure cannot hold it — either the sky burns out or the foreground falls to black. That is what auto exposure bracketing is for. The catch is what happens next: those 3, 5 or 7 frames sit in your library unmerged, because hunting them down and combining them by hand is a chore. MergeHDR does the hunting. It watches your photo library for exposure-bracket sets — frames shot seconds apart at stepped EVs — and flags every one it finds, reading the EXIF your camera already wrote. No manual sorting. No missed brackets. REVIEW BEFORE YOU COMMIT Every merge is yours to shape: • Alignment corrects the small shifts between handheld frames — no tripod required • Four deghosting levels handle moving subjects, rippling water and windblown leaves • Tone-mapping styles set the look, and you can switch after the merge without reprocessing the set • Per-exposure layers with opacity control, so you can see exactly what each frame contributed SEE THE MATH The merge report shows the exposure ladder, how many stops of headroom you recovered and how much of the frame was blown out before the merge — alongside the camera, lens, ISO and focal length read straight from the file. EXPORT Save the full-quality HDR result, or compress it straight to HEIC on the way out using the same on-device pipeline as our other app, RAWtoHEIC — far smaller files, same detail. Results land back in your library beside the originals, with capture date and location carried over. YOUR ORIGINALS STAY YOURS Nothing is deleted behind your back. If you choose to clear out the source brackets after a merge, they move to Recently Deleted with the usual 30-day safety net. EVERYTHING RUNS ON YOUR DEVICE No cloud. No account. No uploads. Detection, alignment, deghosting and tone-mapping all run locally on your iPhone, iPad or Mac. It works on a plane with no signal, and there is no server to breach because there is no server involved. The App Store privacy label reads what it should: Data Not Collected. WORKS WITH Bracket sets from any camera that writes standard EXIF exposure values — Canon, Sony, Nikon and Fujifilm RAW, plus iPhone ProRAW and JPEG. ONE PURCHASE, EVERY DEVICE MergeHDR is a Universal Purchase. Buy once and it unlocks on iPhone, iPad and Mac, with Family Sharing. FREE TO TRY Merge and preview as much as you like. Saving is free for your first 10 exports, up to 5 a day. After that, MergeHDR Pro unlocks unlimited saves. MERGEHDR PRO • Lifetime — $19.99, one-time purchase • Yearly — $9.99 per year, auto-renewing Payment is charged to your Apple Account at confirmation of purchase. A yearly subscription renews automatically unless it is cancelled at least 24 hours before the end of the current period; your account is charged for renewal within 24 hours of the end of that period. Manage or cancel a subscription in your Apple Account settings after purchase. The lifetime option does not renew. Terms of Use: https://mergehdr.app/terms Privacy Policy: https://mergehdr.app/privacy

Screenshots

Struix4 screens
MergeHDR4 screens

Verdict

The call

The clearest difference is in-app purchases: Struix at none against MergeHDR's 2. MergeHDR's advantage is device support (3 vs 1). On price, update cadence, ads and iOS requirement 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. MergeHDR sells 2 in-app purchases, starting at $9.99 per year. Struix asks for nothing beyond the download.

UpkeepUpdate frequency

Struix ships an update every 9 days, MergeHDR every 5 days. The most recent releases landed on October 3, 2026 and October 21, 2026 respectively.

Scorecard2 real differences · 7 level
Struix versus MergeHDR: the parameters behind the verdict, then further details
ParameterStruixMergeHDR
PriceFreeFree
Rating—1.0 (1 ratings) — better
Number of ratings—1 — better
Update frequencyEvery 9 daysEvery 5 days — better
AdsNoNo
In-app purchasesNo — betterYes
Monetization—Free with in-app purchases
DevicesiPhoneiPhone, iPad, Mac — better
Requires iOS18.018.0
Further details — not scored
Size7 MB9 MB
Age rating4+4+
Developer皓逸 祝Sandro Gumz

In-app purchases

None

Struix

No in-app purchases

2 purchases

MergeHDR

Subscriptions1
  • MergeHDR Pro (Yearly)$9.991 Year
One-time1
  • MergeHDR Pro (Lifetime)$19.99

Questions

Is Struix free?
Struix is free to download, with no in-app purchases.
Is MergeHDR free?
MergeHDR is free to download, with in-app purchases available.
Do Struix or MergeHDR have ads?
Neither Struix nor MergeHDR shows ads.
Which is updated more often, Struix or MergeHDR?
Struix ships an update every 9 days, and MergeHDR every 5 days. Most recently, Struix was updated on October 3, 2026 and MergeHDR on October 21, 2026.

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