Comparison

Protractor vs KeyLingo

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

Head to head
About

Protractor

Features
Read full description

PAID ACCESS REQUIRED Protractor is a paid app. A weekly or yearly auto-renewable subscription, or a one-time lifetime purchase, is required to use every feature after onboarding. There is no free version and no free trial. Measure any angle without a physical protractor. Drag two arms across the screen, aim the camera at a real object, or rest your phone on a slope and read the tilt live. Most angle apps give you one trick. Protractor gives you three measuring surfaces in one app โ€” an on-screen protractor for photos and drawings, a see-through camera overlay for real objects, and a motion-sensor inclinometer for surfaces you can put your phone on. Every reading comes out in degrees, radians or percent grade, and roof work gets the rise-in-12 pitch on the same screen. WHAT YOU GET - Read the exact degree of any corner on a photo or drawing by dragging two arms and the vertex onto it - Point the camera at a wall, ramp, roof edge or shelf and measure the angle right on the live view - Turn your phone into a digital level that shows pitch, roll, percent grade and roof pitch as rise:12 at once - Lock a reading with Hold or Freeze so the number stays put while you climb down or move the phone - Keep every measurement in History with a photo thumbnail, plus your saved count, average and widest angle - Switch between degrees, radians and grade in one tap, with a built-in conversion table for common values PERFECT FOR - DIY and home projects: shelves, picture rails, ramps, furniture - Roofing, decking and construction: slope, grade and pitch checks - Woodworking and metalwork: bevels, miters and corner angles - Students and teachers measuring angles on diagrams and photos WHY NOT JUST USE A PLASTIC PROTRACTOR A plastic protractor only works on paper, only reads what fits inside its arc, and is never in your pocket when the roof needs checking. This one measures on a photo, through the camera, or straight off a surface โ€” and it remembers every reading instead of you writing them on a scrap of wood. PRIVACY Everything is measured and stored on your device. No account, no sign-up, no cloud upload of your photos or readings. The camera feed is used only to draw the protractor on top of it, and the app works with no internet connection. FULL ACCESS Full access unlocks the camera protractor, the live inclinometer, saved measurement history and all angle units. It is offered as a weekly subscription, a yearly subscription, or a one-time lifetime purchase. Your exact plan and price are shown before you confirm, and subscriptions renew until cancelled in your App Store settings. Open Protractor, point it at the next angle you need, and get the number in seconds. Terms of Use (EULA): https://web-levi.web.app/terms Privacy Policy: https://web-levi.web.app/privacy-policy Questions? Email tphuc.work@gmail.com

About

KeyLingo

Translate messages in real-time without switching apps. This keyboard app displays translations directly as you type, allowing for instant insertion with a single tap. Communicate seamlessly across languages in any application.

Highlights
  • Real-time translation as you type
  • One-tap translation insertion
  • Use in any app with a keyboard
  • Tone adjustment (Pro feature)
  • No app switching required
Features
Read full description

Stop switching apps to translate. KeyLingo translates right inside your keyboard. Type a message, pause, and the translation appears above the keyboard. Tap it to insert. HOW IT WORKS 1. Open any app with a text field: Messages, KakaoTalk, Instagram DMs and more 2. Switch to the KeyLingo keyboard with the globe key 3. Type in Korean or English 4. Tap the translation above the keyboard to insert it WHO IT'S FOR - Living in Korea and messaging in Korean - Chatting with Korean friends, partners or coworkers - Talking with customers or partners across the language gap FEATURES - Translation as you type - Tap once to insert - Tone options: Professional, Friendly, Polite (Pro) - Works in any app where the keyboard opens PLANS Free: 15 translations per day Pro: Unlimited translations and tone options. Pricing is shown in the app. Cancel anytime in Settings > Apple ID > Subscriptions. Subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period. PRIVACY KeyLingo does not store what you type. - No keystroke logging - Only the text you translate is sent, over an encrypted connection - Text is never stored, logged, sold, or used for ads "Allow Full Access" is needed only so the keyboard can reach our translation server. Korean and English only.

Screenshots

Protractor4 screens
KeyLingo4 screens

Verdict

The call

Protractor and KeyLingo are too close to call on the numbers: across 6 compared parameters โ€” price, update cadence, ads and in-app purchases among them โ€” neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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

CostPrice ยท In-app purchases ยท Ads ยท Monetization

Both are free to download. Protractor sells 3 in-app purchases, starting at $4.99 per 7 days and KeyLingo 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

Protractor ships an update every 6 weeks, KeyLingo every 4 weeks. The most recent releases landed on October 30, 2026 and October 25, 2026 respectively.

ScorecardNo meaningful differences
Protractor versus KeyLingo: the parameters behind the verdict, then further details
ParameterProtractorKeyLingo
PriceFreeFree
Positive reviewsโ€”100.0% of reviews
Update frequencyEvery 6 weeksEvery 4 weeks โ€” better
AdsNoNo
In-app purchasesYesYes
Monetizationโ€”Freemium
DevicesiPhoneiPhone, iPad โ€” better
Requires iOS17.016.0 โ€” better
Further details โ€” not scored
Size5 MB6 MB
Age rating4+4+
DeveloperPhuc PhamSLAM Co.

In-app purchases

3 purchases

Protractor

Subscriptions2
  • Incline Gauge Weekly$4.997 Days
  • Roof Pitch Yearly$24.991 Year
One-time1
  • Bevel & Degree, Pay Once$49.99
2 purchases

KeyLingo

Subscriptions2
  • KeyLingo Pro7 Days trial$2.991 Month
  • KeyLingo Pro7 Days trial$19.991 Year

Questions

Is Protractor free?
Protractor is free to download, with in-app purchases available.
Is KeyLingo free?
KeyLingo is free to download, with in-app purchases available.
Do Protractor or KeyLingo have ads?
Neither Protractor nor KeyLingo shows ads.
Which is updated more often, Protractor or KeyLingo?
Protractor ships an update every 6 weeks, and KeyLingo every 4 weeks. Most recently, Protractor was updated on October 30, 2026 and KeyLingo on October 25, 2026.

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