You can find this app in the iTunes app store at this link
https://itunes.apple.com/us/app/google-drive/id507874739?mt=8
You can find this app in Google Play at this link
https://play.google.com/store/apps/details?id=com.google.android.apps.docs&hl=en
You can find out more information about Explain Everything at http://www.explaineverything.com/
You can find this app in the iTunes apps store at this link https://itunes.apple.com/us/app/explain-everything/id431493086?mt=8