If you have a Google account (Gmail, YouTube, etc), you really should use the Google Photos app to auto-backup all pictures you take to your Google account. Google gives you unlimited storage of photos up to 2048x2048 in resolution, and (if they haven't changed it) videos up to 1080p and 15 minutes. They also give you up to 15GB of storage on Drive for free if your photos or video exceed these limits. Losing photos and videos seems to be the most common form of data loss people suffer, so setting up Google Photos to auto-backup this way prevents loss of those photos just because you lost your phone.
If you have an Amazon Prime account, Prime includes Prime Photos, which gives you unlimited storage of photos of any resolution. So it's preferable to backup your phone's photos that way. Just install the Prime Photos app and configure it to make backups to your Prime account.