Concepts are just ways of thinking and doing that improve our creation and troubleshooting of apps, and how we get data into and out of App Inventor. Here's a quick overview of three important concepts.
The Blocks Editor gives us several features making incremental testing (looking at one part of our apps) and bug fixing easy. Here they are:
Incremental development, meaning we see changes in real time on our phones as we change things in both Design and in the Blocks Editor. In the following screenshot is an example of this. Right-clicking on a block brings up a menu that:
Lets us add notes to ourselves and others looking at our source blocks, explaining what it does and why it's there.
Deactivates the block temporarily as a test to see if it's causing an error.
Remove Complaint (grayed out) removes an error message on the blocks. You'll use this one least of all because App Inventor prevents you from making most errors involving plugging...