When downloading an application from Google Play while using mobile / cellular network, the download may fail and Google Play reports "error 495". In my case, the fix was to enable background data for the "Media" application (I restrict almost all applications from downloading background data on my phone).
- Navigate to Settings, Data Usage.
- Select the mobile operator tab.
- Scroll down until you find "Media" application. If has "restricted" next to it, it is prevented from downloading background data, so enable it and try to install your application again.