Leveraging the Salesforce standard UIs and tools

Salesforce puts a lot of effort into its desktop: and mobile-based UIs. These declarative UIs and related UI builder tools are the first to see advancements, such as the ability to dynamically display content based on expressions. These standard UIs and tools are also the primary method by which administrators or developers will customize your application’s appearance further after installation. Furthermore, the UI will evolve with Salesforce’s frequent updates. In some cases, new features become available to your users without you even updating your application.

In general, aspects of your application that already leveraged the standard UI in Salesforce Classic will just work fine in LEX without changes, and will also automatically adopt the fresh look and feel. However, if you have utilized Visualforce extensively and/or used unsupported features, such as JavaScript Custom Buttons, you will have to make some...