Blauwtoffie

Simple &
useful apps.

A hobbyist developer creating privacy-first apps and tools for iOS, Android, and the web.

Products

Dutch government data via one API. BAG addresses, VIES VAT, RDW vehicle data, energy labels, NS disruptions and more — one key, one request.

Dutch wealth tracking and tax insight. Box 1, 2 & 3 calculations, FIRE planner and more — all offline, no accounts.

Swap exactly one letter in a 5-letter word to reach the target. Curated levels and infinite puzzles across 8 languages.

The language quiz game. Hear a word, guess the language. 30+ languages, Classic and Journey modes, global leaderboard.