How to merge two JPEG files back into a single JPEG (Both sides of a receipt in single image) How to merge two JPEG files back into a single JPEG (Both sides of a receipt in single image) without using any third party software like Gimp etc...
constraints/situation in my case

I had only 2 images to merge, not more
both images were A5 size and I wanted to merge into A4
No third party software. Only pre-installed OS X software to be used.
process to be simple enough for any OS X user
Process followed

select both source JPEG files in finder
Open them together in preview app
Print from preview app to see the print option dialog box
Configure print layout to output 2 pages in single sheet
Select &quot;Open PDF in Preview&quot; from the PDF dropdown menu (a new preview document opens with both source images in a single page)
Save this untitled document as JPEG

I hope this helps. Feel free here to post any other way than this, that might help.

update: For more technically savvy users, using imagemagick :)
convert image1 image2 +append result