You can find Gacha Life APK file at APKpure. APKpure is one of the most famous APK distributing platform.
Once you download the file, you need to install it to your phone. After that you can play Gacha Life.
Here is the link to Gacha Life APKpure page.
You don't have to since you can find Gacha Life in AppStore and Google Playstore. On the Lunime official website, you can install Gacha Life for PC as well.
Gacha Life is a F2P game. Lunime, the team developed Gacha Life, has released only F2P games so far.
Note that you can make in-app purchase to roll a gacha.
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