You're kidding me right? Android applications are allowed to run daemons that will continue to run if you like it or not. [1] Due to Google's lax review process basically you can write a virus and post it to the store.
demon (long running task in the background) != virus
Virus' primary function is to replicate itself and infect other hosts. You can not simply install apps (or viruses) on other mobile devices without user intervention. Also viruses need access to system and/or other apps to be able to propagate itself, which is not the case on mobile platforms.
None of that things is true for demons.
Btw, iOS also has long running processes if you register proper functionality (VoIP, background download..) when submitting the app to App Store. Also iOS and Android apps can be awaken from the server and perform tasks without user noticing it.
Virus' primary function is to replicate itself and infect other hosts. You can not simply install apps (or viruses) on other mobile devices without user intervention. Also viruses need access to system and/or other apps to be able to propagate itself, which is not the case on mobile platforms.
None of that things is true for demons.
Btw, iOS also has long running processes if you register proper functionality (VoIP, background download..) when submitting the app to App Store. Also iOS and Android apps can be awaken from the server and perform tasks without user noticing it.