iTunes is the native application. Just ensure you are signed in with your Apple ID.
If you subscribe to or iTunes Match , you don't need a cable. Once you download the M4A to your computer, turn on "Sync Library" on your iPhone (Settings > Music). The file will stream or download wirelessly to your phone automatically. itunes m4a music download install
M4P is an older, DRM-protected file. You cannot install M4P files on unauthorized devices. You must upgrade the file via iTunes Plus (usually a small fee per song or album) to convert it to DRM-free M4A. iTunes is the native application
Alternatively, you can import CDs into M4A format. Insert a CD, open iTunes/Apple Music, and go to . Choose “AAC Encoder” and select a quality (e.g., “iTunes Plus” at 256 kbps). Then, click “Import CD.” Each track will be saved as an M4A file. Once you download the M4A to your computer,