printing on 8.5x11 paper from mobile device

[Lynda1972]

i have a hp envy photo 7155

when I print a document from my I phone or I pad it prints on only 4x6 paper when I try to change this it will not let me click on letter size or not give me an option at all.  

I would like to be able to print pdf files from my emails

[TEJ1602]

@Lynda1972, Welcome to HP Support Community!

Are you using the AirPrint or HP Smart App to print from?

If using HP Smart App, follow the steps below-

1. On the HP Smart app home screen, tap the Print Document or Print Photo tile.

2. Select a document or photo you want to print from your mobile device.

   The Preview screen displays.

3. Tap the preview image to edit the document or photo.

4. Tap Print.

   The Print Preview screen displays.

5. Tap the image to access the Transformation menu where you can resize and rotate the image.

6. After you resize or rotate the image, tap Done to return to the Print Preview screen.

7. On the Print Preview screen, slide up the panel that displays the printer name above the print toolbar.

   The available print settings display.

   Depending on your printer features, you can set the number of copies, paper size, color option, page range, print quality, and specify the double-sided option.

8. Tap Print.

Keep me posted for further assistance.