Comparison

Isosceles Triangle PRO vs InkDeck

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

Head to head
About

Isosceles Triangle PRO

Calculate all properties of an isosceles triangle, whether acute or obtuse. Input known values to see formulas and results. Supports decimals, fractions, and step-by-step solutions with history saving and sharing.

Highlights
  • Calculate all isosceles triangle quantities
  • Display formulas for calculations
  • Supports acute and obtuse triangles
  • Handles decimals and fractions
  • Step-by-step solution display
  • History function for saved calculations
  • Adjustable decimal places
Features
Read full description

The best app to calculate all quantities of an isosceles triangle. You must enter some quantities like an angle and a length. The algorithm searches the formulas of the missing quantities, shows them and calculates the results. The calculation of an isosceles triangle depends on one certain characteristic. Either it is obtuse angled or acute angled. Both is handled in this app. You just have to touch the button to switch the appearance of your isosceles triangle. The length of the decimal place can be changed. The algorithm shows when rounding or wrong values lead to an opposition. Decimals and fractions are supported. The solution is shown step by step. All calculations are stored in the history. The final solution can be shared. [ Content ] - all important quantities for the isosceles triangle - formulas for all important quantities of an isosceles triangle - infographic to illustrate the topic - search bar to find the desired quantity - history function to save the input - detailed solution - positive numbers, decimals and fractions are supported - changeable decimal place - changeable appearance of your triangle (obtuse angled - acute angled) - no ads! [ Usage ] - there are several fields for entering the values ​​using a special keyboard - if values are missing, all fields are highlighted in orange - if values are conflicting or wrong (e.g. negative lengths), one affected field is highlighted in red - every value must be positive - if a value is no number, it is highlighted in red - the entries in the history can be deleted or sorted manually - if you select an entry in the history, it will be loaded automatically for the calculation - the entire history can be deleted by pressing a button - solutions can be shared [ Acute angled ] - gamma must be less than 90° - alpha must be greater than 45° and less than 90° [ Obtuse angled ] - gamma must be greater than or equal 90° and less than 180° - alpha must be less than or equal 45°

About

InkDeck

Create and study flashcards with handwritten notes and drawings. Supports spaced repetition, multiple study modes, and engaging games to make learning fun. Syncs across devices via iCloud without an account.

Highlights
  • Handwritten notes and drawings
  • Spaced repetition system
  • Multiple study modes (Quiz, Typing, Match)
  • Four built-in study games
  • Import Anki and CSV decks
  • Progress tracking and stats
  • iCloud sync across devices
Features
Read full description

InkDeck is the flashcard app you write by hand. Every card is a real drawing canvas — sketch diagrams, write formulas and practice characters with Apple Pencil or your finger, on iPhone, iPad and Mac. Free to start. InkDeck Pro is a one-time purchase — no subscription. STUDY FIVE WAYS • Review — flip and rate yourself; spaced repetition schedules every card at the right moment, with reminders so you never miss a session • Quiz — four-choice questions with instant feedback • Typing — type the answer; fuzzy matching forgives small typos • Match — pair terms in Quick Fire, Batch Submit or Sliding Window • Cloze — fill in the blank from context SIX GAMES MADE FROM YOUR CARDS Card Shooter, Balloon Pop, Pair Hunt, Word Forge, Deckle and Letter Trail turn any deck into a game, so review stops feeling like review. WRITE IT, DON'T JUST TYPE IT • Handwriting and typed text on the same card • Lasso to select, move and resize your ink • Images, backgrounds and color gradients • Record audio for pronunciation practice • Markdown for formatted text • Pick how your cards flip BRING YOUR DECKS Import Anki .apkg decks with their images and audio, or start from a CSV file. Ask the AI tool you already use to write cards, then paste them straight in. Share decks with the .inkdeck format. TRACK YOUR PROGRESS A calendar heatmap, review history, accuracy stats and retention curves show exactly how you're improving. Keep your study streak alive. EVERY DEVICE, NO ACCOUNT Your decks sync through iCloud across iPhone, iPad and Mac. No sign-up. Available in 11 languages: English, Spanish, French, German, Japanese, Korean, Portuguese, Russian, Turkish, Arabic and Chinese. The free plan includes 3 sets of up to 10 cards each. InkDeck Pro removes the limits with a single purchase. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://inkdeck.gittrics.com/privacy

Screenshots

Isosceles Triangle PRO4 screens
InkDeck4 screens

Verdict

The call

The clearest difference is price: InkDeck at Free against Isosceles Triangle PRO's $2.99. InkDeck also leads on update cadence (every 9 days vs monthly). Isosceles Triangle PRO's advantage is rating (5.0 vs 4.0) and in-app purchases (none vs 3). On ratings volume, 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

InkDeck is free to download; Isosceles Triangle PRO costs $2.99 up front. InkDeck sells 3 in-app purchases, starting at $2.99 per month. Isosceles Triangle PRO asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Isosceles Triangle PRO holds the better App Store score, 5.0 against 4.0. Both are backed by a comparable volume of ratings — 2 and 1 respectively.

UpkeepUpdate frequency

Isosceles Triangle PRO ships an update monthly, InkDeck every 9 days. The most recent releases landed on October 21, 2026 and October 5, 2026 respectively.

Scorecard5 real differences · 4 level
Isosceles Triangle PRO versus InkDeck: the parameters behind the verdict, then further details
ParameterIsosceles Triangle PROInkDeck
Price$2.99Free — better
Rating5.0 (2 ratings) — better4.0 (1 ratings)
Number of ratings2 — better1
Update frequencyMonthlyEvery 9 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFree with in-app purchases — better
DevicesiPhone, iPad, iPodiPhone, iPad, Mac
Requires iOS15.0 — better16.0
Further details — not scored
Size180 MB21 MB
Age rating4+4+
DeveloperGlindemann, Sennoun, Langer GbRMuhammad Mukhtar

Customer experience

Isosceles Triangle PRO

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

InkDeck

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Isosceles Triangle PRO

No in-app purchases

3 purchases

InkDeck

Subscriptions2
  • App Access For 1 Month7 Days trial$2.991 Month
  • App Access For 1 Year7 Days trial$24.991 Year
One-time1
  • Unlimited cards$7.99

Questions

Is Isosceles Triangle PRO free?
Isosceles Triangle PRO costs $2.99, with no in-app purchases.
Is InkDeck free?
InkDeck is free to download, with in-app purchases available.
Which has better reviews, Isosceles Triangle PRO or InkDeck?
Isosceles Triangle PRO is rated higher. Isosceles Triangle PRO averages 5.0 out of 5 from 2 ratings, while InkDeck averages 4.0 from 1 ratings.
Do Isosceles Triangle PRO or InkDeck have ads?
Neither Isosceles Triangle PRO nor InkDeck shows ads.
Which is updated more often, Isosceles Triangle PRO or InkDeck?
Isosceles Triangle PRO ships an update monthly, and InkDeck every 9 days. Most recently, Isosceles Triangle PRO was updated on October 21, 2026 and InkDeck on October 5, 2026.

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