If you want Amazon to add integration with Wemo, Hue, Nest or an open API for developers, please write to Amazon directly.
If it very important that you do this through the Echo App. What you write will be extremely valuable since only Echo owners can contact Amazon this way. They will know that you are an Echo owner through the Amazon account that's registered with your Echo.
1. In the Echo App, touch the menu icon.
2. At the bottom of the menu items, touch "General Feedback"
3. For the issue, touch "New Feature Request"
4. Type what you want to say and send it.