It is possible to consume standard MS created API's with PowerApps. It is also possible to create an API page as an extension and publish it to Business Central. I would like to have these custom API's available to use with PowerApps. We have currently customer cases where we need for example enter lines to Job Journals where this would be extremely handy, and would improve customer satisfaction.
Comments
Thank you for your feedback. We are considering adding it to our longer term roadmap.
Your help is greatly appreciated,
Brian Meier
PM, Microsoft 
Category: Reports and Business Intelligence
I've been looking at the API side of things and you can create custom APIs.
https://docs.microsoft.com/en-us/dynamics365/business-central/dev-itpro/developer/devenv-api-pagetype
However, when creating one that tries to use the Configuration Template (as per the below code):
GraphMgtGeneralTools.ProcessNewRecordFromAPI(RecRef,TempFieldSet,CurrentDateTime);
I get the AL problem of
The type or method 'ProcessNewRecordFromAPI' cannot be used for 'Extension' development.Yet, this is used in the standard "Customer Entity" API Page.
Not yet investigated why that function imposes this limitation
Category: Reports and Business Intelligence
Business Central Team (administrator) on 5/17/2022 1:24:23 PM