iOS 10.3.2 has been released and it is highly recommended to do an immediate update.
It fixes an embarrassingly large number of vulnerabilities as well as some bugs (but not all) left over from iOS 10.3
If you get an email or text with any link to do this update I would recommend you ignore it (I got one of TalkTalk just after I updated, it might be genuine but why take the risk?). Just go to settings-general-software update
It is yet another big update and does take quite a bit of time, make sure your battery is topped up etc.