If you receive the error:
{"errorCode":"NOT_AVAILABLE_ON_CURRENT_PLAN","errorMessage":"Application is not active. Check Online Store Control Panel > Apps > My apps for details."} after selecting to add the Webship app on Ecwid, this is due to being on the basic Ecwid plan. You must have an Ecwid ‘Venture’ plan or higher in order to have App access for your store.