For those unfamiliar with the Yalp Store, it's an open source third-party app store that mainly scrapes the Google Play Store for downloads, while avoiding the use of any Google Play Services. It can allow you to install Play Store apps on your phone without needing to log into a Google account on your phone. As a byproduct of how Yalp works, it's also made downloading the likes of Nvidia Shield games on any device possible while remaining entirely legal. While the Yalp Store is a great app, it lacks a pretty interface because the developer wants it to run on any device from Android 2.x up meaning that it cannot implement Material Design. That's where "Galaxy" by XDA Senior Member WryOrean comes in—it's a fork of Sergey Yeriomin's Yalp Store which aims to bring a Material Design interface to the app.
Note that the Yalp Store and all of its forks are in a grey area in terms of how they are viewed by Google and that there is always a risk of your account being terminated when using third party software to access Google's APIs.
We haven't heard of that ever happening yet, though, so there's no need to panic until it actually starts to happen.
Galaxy follows Material Design guidelines and as a result, better resembles the Google Play Store.
For those who want to avoid the Google Play Store, you can find Galaxy on XDA Labs or on our Android Apps & Games forums below. It's really only useful in a scenario where you've de-Googleified your device, either with the likes of MicroG or flashing certain custom ROMs like this LineageOS fork.
The Yalp Store provides its own credentials to download apps with, but you can choose to use your own Google account if you desire. Regardless, it will automatically update your apps just like the Google Play Store and it even provides file sizes, download counts, and app ratings.
[appbox xda in.dragons.galaxy]