OPQRcoder vs UnitPro
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
OPQRcoder
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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.
UnitPro
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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
Verdict
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
Both are free to download. OPQRcoder sells 1 one-off in-app purchase. UnitPro asks for nothing beyond the download.
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.
| Parameter | OPQRcoder | UnitPro |
|---|---|---|
| Price | Free | Free |
| Update frequency | Every 16 months | Every 3 weeks — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Devices | iPhone, iPad, iPod — better | iPhone, iPod |
| Requires iOS | 15.1 | 15.0 — better |
| Further details — not scored | ||
| Size | 37 MB | 1 MB |
| Age rating | 9+ | 4+ |
| Developer | Takaho Endo | 晓 éƒ |
In-app purchases
OPQRcoder
- OPQRcoder Pro$1.99
UnitPro
No in-app purchases
Questions
Is OPQRcoder free?
Is UnitPro free?
Do OPQRcoder or UnitPro have ads?
Which is updated more often, OPQRcoder or UnitPro?
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