How do I stop my cell phone from freezing when I try to access my inbox?

what i usually do when my phone freezes is that i turn it off. then open the back of the phone and then take out my battery and the sim card. clean them and let them out for a little bit then after some time put everything back and it should work. sometimes the phones just freeze when they have to much going on. for example your txtng then get a call or online and your phone gets a txt things like that.