Comparison

OPQRcoder vs UnitPro

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

Head to head
About

OPQRcoder

Features
Read full description

Standard QR codes contain unused "padding" bytes after the encoded data. OPQR writes your image into those bytes — invisible to scanners, visible to eyes. Select an image or take a photo and generate code with any text.

About

UnitPro

Features
Read full description

The only unit converter you'll ever need. UnitPro handles 10 categories of conversions — all offline, no ads, no accounts. SUPPORTED CATEGORIES: • Length (m, ft, mi, km, in...) • Mass (kg, lb, oz, g, ton...) • Temperature (°C, °F, K) • Area (m², ft², acre, hectare...) • Volume (L, gal, mL, cup...) • Speed (km/h, mph, m/s, knot...) • Time (s, min, hr, day, week...) • Data (B, KB, MB, GB, TB...) • Energy (J, cal, kWh, BTU...) • Currency (30+ currencies with offline snapshots) FEATURES: • Smart input with unit suggestions • One-tap reverse and copy/share • 200-entry searchable history • Favorites with Quick Pick on home • Bilingual: English and Chinese • Works 100% offline — perfect for travel Whether you're an engineer doing precise calculations, a traveler converting currencies on a plane, or a student working on homework — UnitPro has you covered.

Screenshots

OPQRcoder3 screens
UnitPro4 screens

Verdict

The call

The clearest difference is in-app purchases: UnitPro at none against OPQRcoder's 1. UnitPro also leads on update cadence (every 3 weeks vs every 16 months). On price, ads, device support 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. OPQRcoder sells 1 one-off in-app purchase. UnitPro asks for nothing beyond the download.

UpkeepUpdate frequency

OPQRcoder ships an update every 16 months, UnitPro every 3 weeks. The most recent releases landed on June 6, 2026 and September 9, 2026 respectively.

Scorecard2 real differences · 4 level
OPQRcoder versus UnitPro: the parameters behind the verdict, then further details
ParameterOPQRcoderUnitPro
PriceFreeFree
Update frequencyEvery 16 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesYesNo — better
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.115.0 — better
Further details — not scored
Size37 MB1 MB
Age rating9+4+
DeveloperTakaho Endo晓 郭

In-app purchases

1 purchases

OPQRcoder

One-time1
  • OPQRcoder Pro$1.99
None

UnitPro

No in-app purchases

Questions

Is OPQRcoder free?
OPQRcoder is free to download, with in-app purchases available.
Is UnitPro free?
UnitPro is free to download, with no in-app purchases.
Do OPQRcoder or UnitPro have ads?
Neither OPQRcoder nor UnitPro shows ads.
Which is updated more often, OPQRcoder or UnitPro?
OPQRcoder ships an update every 16 months, and UnitPro every 3 weeks. Most recently, OPQRcoder was updated on June 6, 2026 and UnitPro on September 9, 2026.

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