There are dozens of reports and complaints in the Google Web Search Help forums that the Google iOS App keeps logging users out over and over again. This can be frustrating to those who want to use personalized features such as Google Now or other saved preferences.
One user said it is even more frustrating for him because not only does it log him out, he has to go through the two-factor authentication process, each and every time, to log back in.
I use Google 2-factor authentication. About once a day, the iOS Google Search App logs me out of my account forcing me to log back in again. In the end I am giving up using Google Now functionality on iOS. Does anyone have any tips to fix or is this a known bug?
The bug was reported a month and a half ago and Google did not acknowledge it until a few days ago.
Jessica from Google said:
Thanks to everyone for submitting reports of it here. We've confirmed that it's an issue and we're working on a fix. I'll provide an update when we've got one -- in the meantime, thanks for your patience!
So wait it out but not using the app until it is resolved.
Forum discussion at Google Web Search Help.