Storage bleeding

My storage became full a few days ago so I deleted a lot of photos, videos, conversations, safari history etc freeing up 1.5gb of the 6 available on my phone.

Then a few days later, I get the low storage notification again. 1.5gb went pretty fast. So I check and my remaining 35mb slowly vanished after about an hour. So

I check online and read to backup and wipe everything (to remove the 'other' file that was 4.5gb) which I did and it successfully freed up about 4gb. However

An hour later that decreased to 2.7gb free and it's still dropping!? What is going on please. I only have about 6 extra apps, and they're the usual bunch. Clash of

Clans, Facebook, imdb, Instagram, whatsapp and snapchat, all of which I've wiped and re-uploaded, but no change. any ideas?