Retention period & security for uploaded media

Hello.

  1. For how long will glide keep the media users upload using the App? E.g. pictures or videos or any file for that matter uploaded via a glide app.

  2. Will the glide engine remove files and URLs which are of no use? E.g. was used in a record but then record got deleted or changed.

  3. I believe the URLs of uploaded media are public. Is that right? So how safe it is to upload an image of a financial document (check) or medical document (insurance card)?

Appreciate your input.