If any of these so called antivirus programs for Android can prove they do anything particularly useful, I may endorse one. At this time, there are no viruses on Android, and malware is detected and removed by Google. Once new malware comes out, these apps have no way of knowing it, and cannot protect you.
The best these apps can do is give you some uninformed peace of mind, the worst is they can bog down your system. For now, I cannot recommend them.