Steganography is the practice of concealing a file, message, image, or video within another file, message, image, or video. This has often been used to pass on viruses to computers. A "simple click on the pic and your computer is sick" (sorry had to put that in).
Many smart phone users believed they were immune from this problem as the program was not written for the phones internal operating system (IOS).
Unfortunately you are not safe. There are Steganography programs specifically made for the phones IOS's and people are having their info stolen or worse.
These Steganography programs are being sent by text, email and through social media. Do not just open attachments if you do not know who they are from. Stop randomly doing the Cut, Copy and Paste being asked by some social media posts.