App Inventor Open Source Development

The MIT Center for Mobile Learning is pleased to announce the official free and open-source release of the MIT App Inventor source code at

Our hope is to nurture a robust and active open-source community, now that we have deployed MIT’s large-scale public App Inventor service. We will be updating this site with each new release of MIT App Inventor. We have also posted supporting documentation and will continue to add more as it evolves.  

In addition we have created a forum for the App Inventor open-source developer community. The forum will be managed by MIT App Inventor Development Team Member José Flores. José is enthusiastic about helping this community realize its potential to become the source of creativity that will evolve and extend App Inventor and open the power of mobile apps development to learners and aspiring developers of all ages. We look forward to all of your feedback and questions as we move forward in the development of App Inventor.

Enjoy the code, and Happy Inventing!

Andrew McKinney
MIT Appinventor Technical Lead

Showing 1-21 of 933 topics
Announcing App Inventor Extension Components Hal Abelson 9/22/16
"The arguments are the wrong number of arguments for..." when using long-values Arne Mailand 5:07 PM
Proposal on PhoneCall Status seangx 6:16 AM
Una Ayuda Spinner .java David Valdivia 10/20/16
Can anyone Help me with an Extension? JoezCodes 101 10/19/16
Comprehension: How many threads can be created? 1 or more? What are the process orders like (sequential or parallel)? Arne Mailand 10/17/16
(socket == null) always false Arne Mailand 10/16/16
AppInventor Bug - Invalid Array length!? Arne Mailand 10/16/16
Thread not working Arne Mailand 10/14/16
BYOD ACL list David Thornton 10/14/16
undefined runtime error Arne Mailand 10/9/16
Request for Feedbacks / Suggestions for improvements Arne Mailand 10/9/16
What is this block good for? Arne Mailand 10/9/16
Socket returning method (Extension) possible ?!? Arne Mailand 10/9/16 causes runtime error Arne Mailand 10/8/16
Contribute to the MIT App Inventor Project piyush goel 10/8/16
Cannot start local App Inventor (OS X, Ant 1.9.2, Java 1.8) Arne Mailand 10/4/16
Salmon Sembiring 10/4/16
Getting Error 503 i jane 10/4/16
Many Runtime Errors after placing Extension Arne Mailand 10/3/16
Creating Extensions with AsyncTask (android.os.AsyncTask) possible? Arne Mailand 10/2/16
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