Speed problem

I have been using my ipod since 1-2 years and it has become incrediblay slow. I have an ipod touch 3g and i have to say its much faster than the 4g shockingly. I am running 6.1 and keep it up to date. Please help! It takes so much time to open messages, facetime, even notes! some tips to make it run smoother? thx!🙂