Android: Does Tablets support telephony?

I just came to know to restrict my app only to be downloaded on Phones but not on Tablets I have to enforce the telephony feature into my Manifest file by adding

<uses-feature android:required="true" android:name="android.hardware.telephony"></uses-feature>

Now my questions does the tablets support telephony, Can I make regular calls from tablets. I just came across some posts which says it is possible. If yes the how to restrict the app to get downloaded only on phones not tablets. I am bit confused. Could anybody have the genuine answer for this.

I also read the following post on Android FAQs

What kinds of devices can be Android compatible?

The Android software can be ported to a lot of different kinds of devices, including some on which third-party apps won't run properly. The Android Compatibility Definition Document (CDD) spells out the specific device configurations that will be considered compatible.

For example, though the Android source code could be ported to run on a phone that doesn't have a camera, the CDD requires that in order to be compatible, all phones must have a camera. This allows developers to rely on a consistent set of capabilities when writing their apps.

The CDD will evolve over time to reflect market realities. For instance, the 1.6 CDD only allows cell phones, but the 2.1 CDD开发者_如何学编程 allows devices to omit telephony hardware, allowing for non-phone devices such as tablet-style music players to be compatible. As we make these changes, we will also augment Android Market to allow developers to retain control over where their apps are available. To continue the telephony example, an app that manages SMS text messages would not be useful on a media player, so Android Market allows the developer to restrict that app exclusively to phone devices.

Thanks

Not all tablets support telephony, but some do.

Actually telephony is an "umbrella feature", where the tablet may support some sub-features.

There is a an explanation on this blog post and links for further information.

if you have a PC windows tablet, you can use USB telephony device or so called usb voice modem to create a full featured telephony solutions. Since it uses usb to connect to your tablet and resolve the hardware layer issues.