
These types of image files will not load automatically in ProtonMail, and you'll have to tap "Load remote content" (on iOS) or "Display images" (on Android) in order to view the images. However, emails that use HTML to deliver content - which is pretty much all newsletters and promotional emails you get from websites and companies that you subscribe to - use images hosted online in their emails. Also, if those file types are uploaded as attachments, you will only see the attachment file name, no preview. To clarify, photos, GIFs, and other visual media that are stored in the email directly should load automatically for you. You see two sections on the screen (see the 3rd image below).

Select attachment icon (see image 2) and then select an attachment (either using the camera or files on the device storage). This is a security mechanism that can prevent malicious code from being executed on your system, but it can also be fairly annoying to have to manually load images in email after email. Start composing the email (select address to send from and to send to, fill in subject, write in body). By default, images embedded using external links will not automatically load in any emails that you get with ProtonMail.
