Streamzoo, an alternative to Instagram, has just released the Streamzoo API. According to the documentation, the API uses HTTP calls and returns JSON. It joins 341 photo APIs in the ProgrammableWeb directory.
But why not just use Instagram?
In a recent blogpost listing 25 reasons why Streamzoo beats Instragram by [S]hetalksandroid , several stood out, including more filters (23 to 20), a native collage feature (Instagram requires 3rd party apps to accomplish that), and adding photo titles and descriptions (this is in addition to what Instragram allows, simple captions).
As well as edging out Instagram on features, Streamzoo has the look and feel of a small shop, the kind that is easy to get to know and relate to, the kind that isn't going to grab your content and invade your privacy. Here's an example, their answer to the question, who owns your photos on Streamzoo:
"For any and all uploads to Streamzoo, the original uploader (that means you) retains all ownership and copyrights, provided that the content is original.
Streamzoo may periodically select photos and videos uploaded by users for promotional or other purposes (such as highlighting them in blog posts). However, whenever a user's upload is used by Streamzoo, the owner will be notified. If such usage is unwelcome, feel free to contact us via email, and we will remove your photo or video."
That care for user privacy pervades the site, right down to a feature that lets to tag some photos as private even if you have a public profile.
As Lifehacker concluded, it's surprising that Streamzoo hasn't outpaced Instagram in popularity.