Yes, I think more people casually install Apps on their cell phone, and don't really make sure it is not a virus before installing it like people who use Windows and Mac.
But, there are also not many anti-viruses and security software for cell phones.
I read that some App stores scan or ask someone to test the App before letting it be published on the App store while other App stores are more open and don't have the staff or man power to check every single app for viruses.
I believe the Apple App store for iPhone is more restrictive and remove apps which are spyware, or contain dangerous code.
