Since EzTunes is not on the App Store, you need to "sideload" it. This is completely safe and legal - Apple just makes you jump through some hoops. Follow this guide step by step!
Pick whichever sounds easier to you. Both work the same way!
AltStore is a free app that lets you install apps not on the App Store. It is trusted by millions of users.
Go to altstore.io and click "Download AltServer" for Windows or Mac.
Windows: Run the installer. It will also install iCloud if you do not have it.
Mac: Drag AltServer to your Applications folder.
Plug your iPhone into your computer with a USB cable. If it asks "Trust This Computer?" tap "Trust" and enter your passcode.
Windows: Look for the diamond icon in your taskbar (bottom right, near the clock). Click it.
Mac: Look for the diamond in your menu bar (top right). Click it.
Click the AltServer icon, then "Install AltStore" and select your iPhone. Enter your Apple ID and password when asked. This is safe - it is only used to sign the app.
On your iPhone go to: Settings > General > VPN and Device Management. Find your Apple ID email and tap "Trust".
On your iPhone, go to the EzTunes GitHub page and download the latest IPA file from the Actions tab. Or download on computer and transfer via AirDrop/email.
Get IPA FileOpen the IPA file and choose "Open in AltStore". AltStore will install EzTunes. Done!
Sideloadly is another free tool that works directly from your computer.
Go to sideloadly.io and download for Windows or Mac.
Get the IPA file from GitHub Actions and save it to your computer.
Get IPA FilePlug in your iPhone. Open Sideloadly. Drag the IPA file into Sideloadly.
Type your Apple ID email and click Start. Enter password when asked.
Go to Settings > General > VPN and Device Management, find your email, tap Trust.
Find EzTunes on your home screen and open it. Enjoy your music!
If you get stuck, these resources can help: