Can't download apps & updates; get continous spinning gray circle

I can't download apps or updates. When I try, I get a thin gray continuous spinning circle. Am using iPad Air, ios 8.4. SOLUTIONS I TRIED: tried hard reset several times; did not solve the problem. Checked and rechecked settings to make sure I can accept downloads and updates. Everything was fine. I keep seeing updates available but when I try to download, I get the thin gray spinning circle. Help!