When I wanted to do this, I found the available apps sorely lacking, so I wrote a home screen widget which can do this. The image can be a static one, or you can refresh it from the Internet periodically (e.g. from an RSS feed). You can set it to open a website when clicked, or launch an app of your choice (amongst other things).

The app is called Showr, and it's a free download from Google Play. (There's a "pro" version with more options.)

When I wanted to do this, I found the available apps sorely lacking, so I wrote a home screen widget which can do this. The image can be a static one, or you can refresh it from the Internet periodically (e.g. from an RSS feed). You can set it to open a website when clicked, or launch an app of your choice (amongst other things).

The app is called Showr, and it's a free download from Google Play. (There's a "pro" version with more options.)