Really useful information! Get yourself a cup of tea and spend ten minutes reading!
My Golden Rules:
Note that if deploying image buttons, especially for toolbars, they may have to be defined in pixels (height and width) to minimise distortion. In my experience, square buttons 50pix x 50pix (min 44pix x 44pix) can serve a range of different phone sizes. A Horizontal Scroll Arrangement (aka container) can ensure the User has access to all of the buttons on the toolbar.
Defined and or managed incorrectly, images will take up too much memory and could cause a crash:
Things to look out for:
"Good Housekeeping" pays dividends!
An average of 400,000 Users per month means that you have a lot of competition for the attention of the Power Users (Technical Support Volunteers). Therefore, it is in your best interests to ensure that your help request is very carefully described and where appropriate supported with images and a small Test Project File (.aia) that demonstrates the problem.
If you are communicating with (IOT) hardware such as Arduino, BBC Microbit, Raspberry Pi, Banana Pi -include your Sketch/Script and connectivity (BlueTooth, BlueTooth LE [BLE], Network, WiFi, USB). Include your schematic or circuit diagram too.
If you are having trouble with App Inventor (rather than your work on your App) try this first: MIT: Troubleshooting for App Inventor 2
Description: Tell Us:
How to attach a Project File (.aia) to your Forum Post:
Links to all things App Inventor
GeneralMIT: Setting Up App Inventor
Learning App InventorMIT Beginner Videos
App Inventor for TeachersApp Inventor for Educators
External StorageMIT: Using Google Sheets in MIT App Inventor
Arduino and other Microcontrollers
Hot Tip: Ardunio Sketch (Script): Use println() to separate messages when you transmit.
App Inventor: Set DelimiterByte to 10 in BlueTooth Block.
Check that: Bytes Available > 0 in BlueTooth Block.
Then request -1 bytes to get full message.
Video FormatsMIT: App Inventor: Android Video Player Formats Supported
App Inventor Extensions
Extensions Library maintained by App Inventor Expert Taifun Baer, including his own excellent ProductsPura Vida: App Extensions
How to install an Extension in App Inventor
Example Extension: MIT Bluetooth Lite Edition (BLE) Extension