Answer to "Phone shut down one year ago today. It just came back on! Why?"There might be some moisture on your Android phone which caused to force shutdown your mobile in order to avoid any further damages. One year later, the moisture was completely removed due to warm climate or any other reasons. This is quite simple to understand. You are still free to contact any paranormal activity exeperts or the Exorcist.
Answer to "phone is coming on and staying on "BLU" ,how to fix it?"Have your tried booting in safe mode? A safe mode can help you to diagnise and uninstall the culprit app causing your mobile to stuck on boot screen. Safe mode can also help you to detect if there is any hardware or software issue on the mobile. (1) Power off your mobile (2) Hold the Volume Up+Power key together (3) Release the power buttom once you see the logo on the screen.(keep the volume key holding) This will boot your Mobile in safe mode. Unistall any recent install app which you think migh cause the error. Follow the detailed guide here: Android Safe Mode, What is Safe Mode? How to Use it to diagnose the Android problem.
Answer to "Phone turns on then off after a few seconds"Check for the moisture