Here's how you can get a free printer app for iPad or iPhone from Canon.
1. Go to the Canon Easy-PhotoPrint page in iTunes Preview (or just do a search in the app store on your iOS device).
2. Click the View in iTunes button.
3. Click the Free button to download the app in iTunes.
4. Sync your iPad or iPhone with iTunes.
Here's a description of Canon Easy-PhotoPrint:
"Canon Easy-Photo Print (Canon iEPP) is a free application that allows you to easily and wirelessly*1 print photos from an iPad, iPhone and iPod touch with a compatible Canon PIXMA printer or a Canon compact photo printer SELPHY via a local wireless network (Wi-Fi). Supported printer models are listed below.
You can wirelessly scan*2 and save images from a PIXMA multifunction printer to your iPad, iPhone and iPod touch.
In addition, you can wirelessly print PDF files stored in your iPad, iPhone and iPod touch to a PIXMA or SELPHY printer.
-Easily select from a wide range of paper types and sizes.
-Select multiple photos from your iPad, iPhone or iPod touch and print up to 20 copies at a time.
-Supports both bordered and borderless photo printing.
-Automatically finds printers on a wireless network when launching the Canon iEPP.
-Start the camera in your iPad, iPhone and iPod touch directly from Canon iEPP, then shoot and print photos instantly.
-Scan with a compatible PIXMA multifunction printer and save the data to your iPad, iPhone or iPod touch as PDF or Jpeg.
-Directly print PDF files stored in your iPad, iPhone or iPod touch.
*1. Requires access point to connect the device and PIXMA printers.
*2. Scanning function is supported by MG, MX and MP series of PIXMA multifunction printers.
Canon Inkjet Printers
PIXMA MX890 Series, PIXMA MX710 Series, PIXMA MX510 Series, PIXMA MX430 Series, PIXMA MG8200 Series, PIXMA MG6200 Series, PIXMA MG5300 Series, PIXMA MG4100 Series, PIXMA MG3100 Series, PIXMA MX880 Series, PIXMA MX420 Series, PIXMA MX410 Series, PIXMA MG8100 Series, PIXMA MG6100 Series, PIXMA MG5200 Series, PIXMA MP495/MP499, PIXMA MX870 Series, PIXMA MX350 Series, PIXMA MX340 Series, PIXMA MP990 Series, PIXMA MP640 Series and PIXMA MP560 Series
Canon Compact Photo Printer
Canon PIXMA Inkjet Printer
Available printer settings
-Paper size: Letter (8.5"x11")*3, A4*3, A5, B5, 4"x6" (10x15 cm)*3, 5"x7" (13x18 cm), 8"x10" (20x25 cm), Card 2.16"x3.58" (55x91 mm), Wide 4"x7.1" (101.6x180.6 mm).
-Media type: Plain Paper*3, Photo Paper Plus Glossy II*3, Photo Paper Pro Platinum, Photo Paper Plus Semi-gloss, Photo Paper*3
*3. PIXMA MP495 and MP499 support only these paper types and sizes.
-Bordered/ Borderless print
Canon SELPHY Compact Photo Printer
Supported paper sizes
-Postcard Size, L Size and Card Size
-Bordered/ Borderless print "