The great new Echo Show product has now been available for about a month, and it is time to consider how to write skills which take the best advantage of the Show.
You already know that you use the Alexa Skills Kit to write the voice part of the interface. This is always the starting point for giving any Echo more powers. Even though the Echo Show adds a screen, it is probably wise to still start with your voice interface. Once you have the idea for what your skill is for, stat thinking about the voice interaction model. The Echo Show still uses the Alexa Skills Kit, and by startiing with it, you will still be able to support all the other flavors of Alexa that are available.
The next step is getting the visual display of information right. Amazon recently provided a new article that gives a good background into this. You first choose a template for how that information is displayed. Amazon has thoughtfully provided several templates. Choose the appropriate template for your content. You need to update the JSON template you return from your skill server (usually AWS Lambda functions).