If i update my iphone via OTA, will it delete my apps, files etc. On my iphone?

So 7.0.6 update is now available on idevices, and i want to update my iphone 5. Will it delete my files if i didn't do a backup? My phone is not jailbroken but i have apps that's not in my itunes account. I downloaded paid apps from tongbu (tongbu is like installous, but does require jailbreak). So every time i do a backup, this paid apps from tongbu are not being backed up. So in short, i can't backup this apps.

and one more thing. I already tried to update my iphone via OTA but it does not download the file. It only says "less than 1 minute remaining", something like that… The download bar doesn't even moving and the file size is just 14mb. Does updating via OTA takes much time as with updating with itunes?

No. It is usually quicker depending on your connection & no it doesn't delete anything.