Hi,

Many of the apps on my N9 suddenly refuse to open.

Background:
I was running about 6 apps including music, browser and mail.
It began to lag significantly, and then got stuck completely, with the mail app refusing to respond to both in-app and off-screen swipes.
It remained stuck for about half an hour, after which it started working again.
But now, i can't open many of the apps:
Mail
Browser
Camera
Clock
Gallery
Music
Videos
Some of the apps installed from Store

Following do open:
- Phone
- Messages
- Some of the apps installed from Store

Further background:
My power button does not work, so I can't restart the phone.
The restart app, that i had downloaded in case such situations arise, does not open either.


Any help would be much appreciated..

Thanks,