This application is not compatible with android 5. 0 yet. This is the paid version with no ads and no internet permission. A free version with ads is also available, along with some free plugins.
Get the installation package of Duo 1.0.20140425 that is provided for free and take a look at users' reviews on Droid Informer. The app is built for Android 2.3.3 and higher. The download of this application doesn't contain viruses or any kind of malware. UNCOPT LLC is the developer of the tool which can be found in the Productivity category.