You can use tools like WhatsApp
as they are relatively secure, however you cannot send anything over 100mb. This is fine if you’re sending a large file to another party, but not to court. Once you hit that limit, you’re out of reliable options. You can use email, but it’s not secure at all. A 10MB attachment limit means you’re stuck for anything larger. You can use WeTransfer, but it’s not business oriented, with no branding, and limited audit controls. It also has limited GDPR compliance terms. And of course you can password protect a file. This is cheap, but passwords can be easy to crack, and theres no way to revoke or audit receipt of the file.