Open Source
Algo Phantoms
Practice coding problems and learn data structures on your phone
This comes straight from Algo Phantoms’s own GitHub page — it’s free. Need help installing? →
About this app
Algo Phantoms is a companion app for anyone learning data structures and algorithms. It includes a built-in code editor along with guided pathways and quizzes, so you can practice writing and testing code without needing a laptop nearby.
It's aimed at beginners who want a friendly, structured way to build up their problem-solving skills over time.
From the app’s home page
- See the codeHow it’s made — every line is public
- Questions & commentsTalk with the people who make it
- Report a problemTell the makers something is broken
- All versionsOlder downloads and what changed
- LicenseThe rules for using and sharing it
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