If you recall a few months ago, Google had updated its Switch [to android]' page with more Google apps. This was only a placeholder, seeing as every method detailed on the website basically told you to download the respective app for iOS, and backing up the respective content to the app. Google Photos, Contacts, Google Drive, etc. This didn't really make it easy to switch between devices using any cloud-based methods. The Google Pixel (XL) came with the USB-C OTG adapter to connect any device directly to the Pixel, which would then pull all the pertinent information from your old...
Source: http://www.gsmarena.com/google_makes_it_simpler_to_switch_from_ios_to_android_with_google_drive-news-22158.php