It uses theme engines as a passage to install fonts to the systems. It packages font files (TTF/OTF) at runtime within the app itself to provide one of these packages:

# Fontio works on devices with sysserv patch in 8.0+ ROMs and not Andromeda plugin enabled devices.
Eg: AOSiP 8.1

1. Substratum Theme
2. CMTE Theme
3. Flashable Zip
4. Font Injection (requires root)

1. Substratum Theme
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● To install a substratum theme you need to have a ROM with OMS commits.
● If you are using Substratum Legacy packaging font as a substratum theme will show a blank screen.
● Legacy users can opt-in for 3rd option (i.e.: flashable zip)
● These substratum themes will also not work on Developer Preview versions AGAIN (3rd option) if you have a TWRP/CWM recovery.

2. CMTE Theme
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● These themes work on ROMs which have CyanogenMod Theme Engine only.
● Thus in ROMs 6.0 and below upto Jelly Bean and not 7.0+ ROMs.

3. Flashable Zip
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● This is sort of like an universal solution for changing your font.
● As a wise man said If you got a recovery you can flash a zip. And he was not talking about stock recoveries.

4. Injection (root)
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● Also an universal solution but requires you to enable it from Settings

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| Usage |
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● Select a ttf/otf file from storage. OR Select font from "Font Store".
● Package the font into substratum readable pack.
● Install the pack.
● Enjoy !!

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| Fontio Premium |
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● Have full control over packaging fonts
● Select different fonts for different font type
● Share and request fonts between all Fontio users
● Mix and match multiple fonts in single package
● Save your font configuration locally