seem like your device got some sort of unstable applications installed or the device is stuck on some task or even inresponding (crash) that used up all of your cpu cycle and Ram. This will lead to frozen state just like an old PC. to resolve this for temporary you will need to reboot your device a few times.

try take out the battery for 10 seconds and then put i back in. if any of you installed applications from Extra-dev then uninstall it. Otherwise if it is still the same then i suggested you should do a fresh reflash the device.

good luck buds