FotoJet (www.fotojet.com) is a free web app that lets you quickly create good-looking photo cards, collages and social media arts without any downloading or installing. And free is always good.

The app includes more than 560 designs. Pick one and you've started your project. Click the Collage category to show all the collage templates divided into six styles: Modern, Classic, Art, Holiday, 3D and Creative.

Click the Photo Card category to show all the photo card templates for Anniversary, Baby, Birthday, Father’s Day, Graduation, Thank You, Travel and Wedding. Or click the Social Media category to show the templates for Facebook Cover and Facebook Post.
You can browse all the templates and choose your favorite one by double clicking or by clicking the Choose button.

Next, you can add your own photos from your Mac or from Facebook directly. Click Auto Fill to automatically fill your photos into the template. Or you can directly drag and drop any photo into the blank frame of a template. You can exchange photos between different frames however you want by simply dragging.You can adjust your photos however you like.

Once your collage is done, you can share it via Facebook or save it as a JPG or file PNG.