Montager is perfect for:
+ postcards from the road
+ party highlight pics
+ favorite shots of the kids
+ stuff for sale (craigslist)
+ real estate previews
Montager is a free app, so download it and try it out! If you upgrade to the Pro version (right from within the app) you can hide the watermark, output at higher res (960x640 and 1440x960) and create smooth rounded corners on your photos.
Plus if you go pro you get new 4-image layouts. Sweet!
★★★★★ "Very easy to use and really effective, especially with pics worked on in other apps." - iTunes UK reviewer
★★★★★ "My pics tell a complete story now... Awesome." - iTunes US reviewer
★★★★★ "Très pratique. Une superbe application!" [Very practical. A superbe application!] - iTunes FR reviewer
★★★★ "I sell clothes online so it's a quick collage type editor for the photos I need to post." - iTunes CA reviewer
★★★★ "ilovethisapp" - iTunes MX reviewer
★★★★★ "Consigliatissima!" [Recommended!] - iTunes IT reviewer
Thanks for all the feedback so far! Let me know if you have any more ideas and suggestions for future versions.