Hi ppls. Do you think an antivirus is recommended for smartphones in general and personally, I'm using the N9, so is there any antivirus for it? Thanks all.
The N9 is quite safe from viruses. It cannot get infected unless you allow it to. Hence a little common sense and the usual precautions is all you need. Do not accept connections from unknown devices and do not download and install apps from unreliable sources.
Thats why you should only backup what is absolutely necessary to avoid recontamination. Things like apps settings should be redone from scratch.
However, I am still of the opinion that it is unlikely you have a virus. The system is probably just clogged from too much use and needs a reset to tidy everything up again.