Why is the app download only for smartphones??

my app is listed in google play store. but it can only smartphnesdownload the app, why not download tablets? 
The app does not appear on tablet under google play store, but with a smartphone, you can see the app and download.



Google Play does not recognize apps developed with Android API 3 as being capable of being used on Tablets.   That is not true, but Google Play does what it wants to do.   App Inventor currently uses API 3 (soon to be changed to API 4 for screen size issues if anything else).     AI2 apps do work on Tablets, however the apps can not be downloaded to a Tablet from Google Play, however the app can still be shared:

• Packaging & Sharing Apps

The simple way to share is to email the apk to someone who has a Tablet.

I think there is a third party tool that can modify the AI2 'manifest' so that it fools Google Play.   Here is a possible work-around that might work for you:   Solution for tablets on Google Play by J Martin