Features & Capabilities

150+ tools and decoding tables to help you solve mystery- and multi-caches and make navigational computations, conversions, decodings and text analyses. The number of tools will grow depending your input, so mail us to suggest/request a new tool or decoding table!

  • No additional in-app purchases required
  • No additional charge for features/tools that will be added in future versions.

GCTK features:

CONVERSIONS Base64/Binary/Decimal/Hex to ASCII Binary/Decimal/Hex/Octal conversions Celsius, Fahrenheit and Kelvin D°M'S" conversions Distances Roman numbers

NAVIGATION 2 WPs + 2 bearings = new WP 2 WPs + 2 distances = 2 new WPs (Intersections of 2 circles) 3 WPs + 3 distances = new WP (Intersection of 3 circles) Centroid & surface of triangle Centroid of circle through any 3 WPs Coordinatesystem conversions (3800+ systems!) Crossing lines Distance, bearing, middle of 2 WPs Project a new WP WP/Bearing + WP/Distance = new WP

DECODING: TABLES

Alphabet, Gernreich Alphabet, Latin ASCII Baal horizontal Baal diagonal Bacon Brahmi Chappe Futurama Hexahue HVD code Illuminati cypher Mayan numerical coding Periodical system Pigpen cyphers (3 x) Resistor colorcodes Sign language Signal flags: maritime Signal flags: NATO Signal flags: semaphore Web- & WingDings

  • and approximately 90 more...

DECODING: INTERACTIVE Braille ROT-5/13/47 rotation Cellphone keypad (char to num) Cellphone keypad (num to char) Morse Signlanguage Vigenère

NUMBERS Prime numbers Fibonacci numbers Pi (decimals) e (decimals)

TEXT Frequency analyses a=1, b=2, a=26, b=25, etc Count characters Count words Hint decrypting

OTHER Sudoku solver QR code scanner Barcode scanner

UPCOMING FEATURES:

  • more and other tools depending your input!

User Growth & Download Statistics

App
By:
JW Rijkes
Rating:
4.70
(60)
Version:
5.1.5 Last updated: 2026-02-20
Version code:
882597668
Creation date:
2013-01-20
Compatible devices:
Size:
12.38MB
Price:
1.99
URLs:
Privacy policy
Full description:
See detailed description
Source:
Apple Apps Store
Data ingested on:
2026-06-12
Compare stats and ranking:

Ranking

Contact the developer

Chrome-Stats does not own this Apple app. Please use these information below to contact the Apple app developer.
Developed by:
JW Rijkes
Apple Apps Store
https://apps.apple.com/de/app/geocaching-gctk/id593639170?l=en-GB

User Reviews

Awesome job on this
by us*****, 2026-01-01

Fantastic application. I’ve been using it for many years and it’s bailed me out more times than I can remember. Believe me you need this app in your tool box…
by Ro*****, 2024-12-31

Been using this for years to help work on solving geocaching puzzles. Super easy to use and it is updated regularly. Highly recommend it.
by Bi*****, 2022-02-24
View all user reviews ›

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