Q: How to use Canon Selphy Photo Printer (CP900) to print from iPad 3?

hi

ideally if you want to print from the ipad you should have an airprint enabled printer:

http://support.apple.com/kb/ht4356

however, there are workarounds, you can download a decent third party app to print such as print n share, printcentral or printdirect

Canon has a app in the app store called Canon Easy Print. You print pictures from that app. It has access to your photos on your phone