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Peter Li

Educational app developer, content creator, AI Enthusiast.


  1. NumLock: Math Screen Lock

    NumLock is a fast-paced number puzzle game that pushes your mental math to the limit. A 4×4 grid of number tiles appears with a target number — select two tiles and an operation (+, ×, −, ÷) to combine them. Solve rounds quickly to chain combo multipliers and climb the leaderboards.Features 5 difficulty tiers (Easy to Master), a Daily Challenge shared by all players, Game Center achievements, stats tracking, and a home screen widget. Every puzzle is algorithmically verified to be solvable before you play.

Recent activity

Apr 15, 2026created a post
I built an app that makes you solve math before you can start doomscrolling

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