Downloading of any large file will take up bandwidth. It could be time to look at all your devices using internet/WiFi and update your connection allowance. 475MB is not very much when you look at the size of files that need to be downloaded - especially when it comes to system updates, app updates, etc for 2 phones and a computer or two.
I know about downloading large files. I just didn't know what was downloading to my new phone. There was no indication that something was downloading, but yet my download allowance status was falling faster than usual, up to a point it ran out a couple times when my son first set up his new phone.
I have set up my Airport Express to connect devices, laptops and iPads, other than me and my wife's phones, to connect only during our allotted free download period.
Living out here in rural AK has it's drawbacks and one of them is getting a good ISP with enough bandwidth allowance for daily use for multiple devices and computers. The next and last step up is a 800 MB package that costs $200 a month that I have previously tried for a few months and I found that it wasn't much of an upgrade from our current $80 a month package. Originally, our connection was a 350 MB daily package but with all the trouble I had with our connection, the ISP gave us the 475 MB daily allowance for free + a monthly discount for a year. Anyway, there is a new ISP that just started up but it has less allowance than what we have as a whole each month for a bit more $$. Cell phone data isn't all that great either after finally getting LTE, when previously we had a nonexistent 2G service, that we were being charged for every month just because we had smart phones.
Sorry for the longish post. It seems that after downloading all my apps from the cloud my phone has quit downloading. It's odd because when I started downloading the apps the app was covered over with a circle and a "Loading" showed up under the app when previously there was none. Anyway, my phone has quit using up my data allowance.