Q: How do I upload photos from my android to iCloud?

Unless there is an Android app for that you can't.

The most elegant solution I found is:

1. Setup automatic upload of new photos to Dropbox on your Android device
2. Get Dropbox and IFTTT apps on your iOS device
3. Create an IFTTT recipe to automatically save each new photo from Dropbox to Camera Roll. It is super easy!
4. Voila!