My iPhone deleted all of my photos

I've been experiencing this for years, on several different iPhones (5,5s and my current 6s)

Completely at random as you say, can happen a few times a day, or once every month. My phone becomes unresponsive, can't swipe on the home screen but for some reason the off button still works and the lock screen slider still unlocks it so it's selectively responsive??

Only fix is to force restart it (the home and off button way) which then deletes all my photos and there's no way of knowing how quick iCloud will decide to download them again, sometimes it's straight away, sometimes it's days :/ really wish this would stop happening it's such a pain in the a**.

I'd try one of those 3rd party apps on your computer that are designed to backup data from an iPhone to a computer without the use of iTunes. Just be careful since these programs may have adware or scammy sales pitches attached. Assuming you're using a mac, maybe run it from a guest account and don't type in your mac's password..a lot of times you can run a program without installing it fully just by opening the icon while it still has the eject arrow and not moving it into your Applications folder/directory.

Be careful not to cause more issues when you troubleshoot it, and backup your photos asap then backup your backups! Lots of free photo storage options out there and most emails give your 10-20 gb of space, if that's useful to you.

Go read another post on here (iPhone 6: Apple logo appears, photos disappear, runs slowly) about others saying they had this same issue...I don't see much of a resolution. I'd personally back everything up but not in an iPhone/itunes full backup (be sure to get everything), backup a full iPhone backup in iTunes, and then wipe the phone and add everything back in by hand from the plain files not stored in iTunes just in case there is some "corruption" hanging out in there.

They are on there for sure. The backup file, if you can locate it on your computer's hard drive, is a decent bet for saving a copy of your photos. It shouldn't be too hard, just look for something about the size of the storage on your iPhone which is fairly large for an ancient PC. All of your photos will be in individual folders inside the backup file and labeled a little less than ideally.

Do you use icloud? It gives everyone 50gb of free storage and 100gb is only .99 cents! It's fairly convenient but I'm asking because you say they slowly reappear. That almost sounds as if your photos are coming back to your phone from the iCloud server's copy since it knows that you also keep a copy on your phone which it sees are missing, possibly triggering iCloud to generously (slowly) make a copy for you.

I feel like you have some hardware damage causing the memory to have some issues and icloud is picking up the slack...Maybe it got wet? No clue if this is really the cause but that could explain random deletes. And 30gb of other is almost certainly photos, video, or music and you should probably be able to estimate what it likely is.

Type in manage storage to the search bar on settings and it'll show you the breakdown of your data. I just got out my 6 and have about 5000 photos and 900 videos for 57.2 GB of data so 30 sounds about right for 15,000 photos.

I also have the same issue. All of sudden, all of my picture has been deleted. Also, I could not take pictures because they are not saved. When I connect with PC, there are no pictures left behind in DCMI folder. I also tried to use icloud, bu t notification said i have 20GB of photo but my icloud offers only 5GB. So, I think my photo exist somewhere, but.. I can't find it.

You should regularly sync photos from iPhone to computer.

See this -> Import photos and videos from your iPhone, iPad, or iPod touch - Apple Support

Is there some reason you are till using iOS 9.1?

HHow old is your computer?

SPecifically, which computer, which OS and version?