There is also http://print.milkbooks.com/ They are one image printing API that easily connects to any platform. The fields are very high, as is the price, but this is offset by the super-high quality of the product. You control RRP to lower the price at any time. Once the user has ordered the book, you are no longer involved in the process, since they all process, from payment to a full refund, even if it is damaged during transit.
Thanks to a wide range of products from single art prints to music cards, gallery canvases and photo books, including a number of Moleskine options, the variety is surprisingly diverse, given that they are specialized publishers of art books.
The API is easy to integrate, does not require investment on your part, is a multi-platform platform, handles all aspects of the order process. The API scales as it is processed by Amazon Web Services, so it grows with your company. It is customizable as you can develop your own range of products, however, this requires some investment on your part, and since they always use https on politics, security is also pretty tough.
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