This comes straight from Key Mapper’s own GitHub page, and it’s free. Need help installing?
What it looks like
About this app
Key Mapper lets you change what the volume keys, headset buttons, game controllers and other hardware buttons do: open an app, control music, take a screenshot.
It is especially handy on phones with an extra button nobody uses.
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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