selected case studies

Mobile and web products we have built.

Explore our mobile apps and web products. Each case study covers the product requirements, the features we developed, and the decisions behind them, with screenshots of the interface.

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Case studies in this index
pk case --list
numina 210 levels
wuxing 4,096 line readings
scooter-handbook 40+ causes mapped
numera 8 languages
4 case studies — discuss other work with us_

$ ls ./case-studies

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4 case studies

iOS · Android

Numina

210levels

A math puzzle app with 210 levels across three modes, ten daily teasers, and practice sets built from puzzles a player finds difficult.

React NativeExpoTypeScript

iOS · Android

Wuxing

4,096line readings

Wuxing combines three-coin I Ching readings with a searchable library of 64 hexagrams, a daily almanac, and a journal for saved questions and readings.

FlutterDartRiverpod

Web

Scooter Handbook

40+causes mapped

A Ukrainian-language e-scooter tool for teenage riders, with symptom checks, possible causes, repair estimates, safety warnings, and nearby shops.

ReactNode.jsMongoDB

Web

Numera

8languages

An offline calculator workspace: amounts in words in eight languages, VAT calculations, rent indexation, and late-payment penalties for Ukrainian paperwork.

Next.jsReactTypeScript

$ ./request_portfolio

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