Why is my android face down after rebooting

[AC Question]

I tried to reformat the phone, but it gets stuck in an endless loop after latest software update last night

 

[Rukbat]

Reformatting the entire phone leaves you with hardware tat has no software to run it. A software update n top of that can really mess it up. (There's no "update" software after the reformat.) Bring it to your carrier and see if they can help you.

 

[B. Diddy]

Welcome to Android Central! Which phone? It would help to know what you mean when you say you tried to reformat the phone. Do you mean you did a factory reset? Was the update an official system update pushed to the phone over-the-air, or did you install it manually?