langify is currently able to translate static images in your theme and images in the descriptions of your products, pages, blog posts, etc.
Step 1
Open the page with the image that you want to translate.

Step 2
Now you have to search for the url of the image. Using the Chrome Development Tools makes this an easy task.

Step 3
Copy the url (in this example it is //cdn.shopify.com/s/files/1/0422/0317/products/white-t-shirt_en_1024x1024.jpg?v=1401542248) and create a new "custom content" in langify by clicking "Add new custom content" in the "Translations / Custom" section (http://langify-app.com/customs).

Step 4
Paste in the url of the image that you have copied in step 3.

Step 5
Go to your Shopify -> Content -> Files section and upload your translated image
Step 6
Once uploaded, copy the URL of the translated image by clicking on the "chain link" icon on the far right.
You need only the part of the link after the "https:"
Step 7
Navigate back to the "Translations / Custom" section in langify.
Click the content that you have created in step 5.

Step 8
Translate your image url by pasting in the url that you have copied in step 7 and click "Save".