How to remove "Upgrade avast! Anti-Theft" nag screen

I removed avast software and I am constantly getting nagged by this software to upgrade.
can you tell me how to remove this nag screen coz its getting really annoying, I also installed this on my wife’s phone and that is now suffering the same problem now, this is not a good advertisement for your software as it’s really off putting, I certainly would not install it on any other device because of that reason.
it is unprofessional to pester people in purchasing your goods, it is basically the same as aggressive cold calling, if you want people to like your software that is certainly not the way forward.
I do not know if I set up an account here or not, so I can not login to web site to change any preference’s if that’s what your going to suggest.
I need a way to remove the info from my phone.
please can you assist me in doing so.
thank you.

As far as I understand you did install avast! mobile security and avast antitheft; after some time you have removed only avast! mobile security and now you are angry because you are getting update notifications for antitheft, which is still installed. So, as you may be have read, after installation of avast antitheft and turning it on, the application will hide itself so you can not reach it from app drawer. You can update the antitheft and use built-in uninstaller or you can install avast! mobile security and use uninstaller from there (located in Antitheft section). You should know your PIN which you have set during the first installation. Mobile security and antitheft are two different applications.