I have installed the latest update of Android. New version is 7.0. I'm experience an error on lock screen. Assume you are getting a call from someone don't answer the call untill it stop or ring 3 times and end the ringing. Now I have put a security pattern on my phone to unlock the device. When I'm trying to unlok the phone unlok screen starts wobble and automatically drawing patterns without any interactions. Then somehow if I unlok the phone automatically opens my apps and highlight words and phone starts like virus affected behaviour. This was due to firmware update. Still samsung didn't test it properly for latest update on S7 it seems. Better wait for stable version release by samsung my advice to keep the marshmallow update untill they release the bug fixed version.