Since my main audio device is Xperia D2105,
I seldom use My ipod touch 4th (iOS 5.1).

You may think iPod touch 4th is obsolete,
but I’m a type of person who use old device until it breaks.

I heard iOS6 was too heavy for this device,
I kept iOS5.1 for a long time.
I use it as audio device, so there is no need to update iOS6.

But these days many apps requires iOS6,
So I finally decided to update my ipod touch 4th.

But After updating it,
Every operation takes much time than before!
How terrible it is!

I changed Language to English.
I have disabled almost all notifications.
It became better.