I heard something recently about it being included in Froyo and I was wondering if there was any truth to it. If there is, it would help me with an app idea greatly.
kgiannakakis
You are probably referring to the Adobe Reader, which is freely available for Android 2.1+. Some devices also have other applications pre-installed for rendering pdf files. See this question on how you can open the default pdf viewer from your application.
Android has a built in framework from Android 5.0 / Lollipop, it's called PDFRenderer.
There's an official example on Google's developer site:
http://developer.android.com/samples/PdfRendererBasic/index.html
来源：https://stackoverflow.com/questions/3969041/does-android-have-a-built-in-pdf-viewer