Gmail Login on iPhone (iOS)

I suggested to a freind that he use Zoho Vault for his passwords, but when trying to use the iPhone app, he only sees the option of "Gapps" login (as well as Zoho login). He doesnt see the full list - Gmail, twitter, Linkedin, facebook.
Is this a problem with the iOS app?
He wants to login with his google accounts (Gmail) but cant from the iPhone

Thanks