Q: why is iPhoto not supported by ios 8.0.2 on my ipad?

iPhoto is not supported on iOS 8, and the app is no longer available in the store - as to why it isn't I don't think that Apple have said.

Migrating from iPhoto on iOS 8 : Migrating from iPhoto for iOS to Photos on iOS 8.

It is most likely not supported because there are new image editing options in the native Photos app included with iOS 8. There will be a similar app coming to the Mac in 2015, which will most likely replace iPhoto for Mac as well.

Yes, Apple announced at WWDC in June that the new Photos app will replace both iPhone and Aperture, iPhoto's professional counterpart.