Phones don't really have unlimited memory. However, there are several ways to expand storage capacity.
One is to use an external storage device, such as a MicroSD card or USB drive.
Another approach is to use a cloud storage service such as Google Drive, Dropbox, or OneDrive. These services allow users to store and access their data in the cloud, saving storage space on their phones. However, it is noted that many cloud services charge fees or offer limited free capacity, and each user needs to choose according to the actual situation.