Though mobile devices with the Android operating system are susceptible to viruses and mobile malware (see the tip, Can Android devices get a mobile virus?), there are several ways you can be proactive in keeping your device – and your personal information – secure. A good starting tip is to use your Android device like you would your PC. Do not click links or download anything from untrusted sources.
Next, consider the source of your app downloads. Though Google Play is the official app store for Android devices, you have the option of installing Android apps and games from other third party sources. The problem with this is that often these third party apps are unsafe and contain malware or other viruses. Therefore, your best bet is to download apps from Google Play only. You can set your device to do so by turning off the “unknown sources” option in your Application Settings. Here’s how: Tap the "Applications" icon on the home screen of your Android phone, scroll to "Settings," and touch the icon or press the "Menu" key on the phone and tap "Settings." Next, touch "Applications." Then, tap "Unknown Sources" if it has a green check in the check box. Press the "Home" key to return to the Android home screen.
Keep in mind when downloading apps from Google Play: there isn’t a guarantee that they are safe, so look at the ratings and read the reviews before downloading.
Lastly, we urge you to install antivirus software on to your device. Lifehacker recently rounded up the best and worst of Android antivirus apps here: http://lifehacker.com/5891576/the-best-and-worst-antivirus-apps-for-android.