@RobertD16693255

I recommend developing an application from App Studio and switching it to Dev Studio whenever required. 

• Using App Studio and defining the skeleton data objects needed by an application
• Using Dev Studio to revise directed inheritance
• Ensuring the quality and extensibility of the data models
• Enabling branch development so that citizen developers can use it
• Conducting branch reviews
• Creating user interface templates for selection in App Studio when configuring a view for a process step
• Decoupling the case layer from:
  • Where the systems of record are
  • What form the systems of record take
  • How the systems of record persist the data
• Creating reusable components and marking as relevant records wherever possible so that they can be discovered in App Studio.
• Application design may require complex positioning of rules and placeholders for these rules in specific rulesets using Dev Studio which empowers the delivery team to pick up the relevant versions from App Studio where possible.
• Ensuring application is designed/implemented as per organization guardrails/best practices set by the Center of Excellence (COE)/LSA team
• Ensure application rules are created in the correct layer and that citizen developers and seasoned developers have the required/correct access.

https://academy.pega.com/topic/application-development-app-studio/v1

https://academy.pega.com/topic/app-studio-development/v1

Please note: If you're building an application using Constellation UI architecture, you must leverage App Studio.