Custom interface to customise card designs, add images, text format and submit in a format which can be recreated later

We need a custom interface built to allow customers to customise either template or completely freestyle design of card - they need to be able to upload images, add text, and submit the design for recreation elsewhere. We have a few versions of such an interface developed in-house, but these do not seem to be cross browser and we constantly experience problems with our "production" version of the application outputting something different to what the customer thought they were creating. Requirements are as follows: > Customer must be able to customise their design exactly as they would like it to appear, on mobile or browser > Design is converted into a format which is emailed to ourselves > "Production" page can parse email and output image file - we currently do this using the html2canvas JS library to output a PNG but we are willing to consider other methods. The application itself must also be easy for our in-house developers to read and modify, the components that we may like to modify are: > Available options > Images used, either for icons or background > Template designs Although we do not want to replicate this exactly, this is the perfect example of the sort of interface we would like to have: [login to view URL]