In iOS 11.2 application I have noticed an unusual behaviour (opening forcefully closed apps, sometimes shows the previously visible view and redirect to the launch screen), I don't know whether it is bug with OS or something else but it can sometime appear in Google app also.
You can find the related video in below link. https://s3.amazonaws.com/uploads.hipchat.com/37040/3355524/7K3EL8N5X55tN8p/ScreenRecording_12-13-2017%2013%3A23.MP4.
Please help me to figure it out whether it is a feature or bug.