hal's blog

Please help up test the new site for sharing App Inventor projects

hal — Fri, 06 Apr 2012 01:19:35 +0000

Ever since App Inventor was launched, there have been many requests for a site where people can exhibit and share their App Inventor work. MIT and University of Massachusetts at Lowell are collaborating on creating such a Gallery site, which we hope to launch later this year.

Right now, we are looking for volunteer testers to provide feedback on the site and to help shake it down.

When the App Inventor service was released from MIT, and before that from Google, our testers were essential in getting the system launched. And the same will be true for this Gallery. So we're forward to your active -- and critically important -- participation.

For details, see the post by Prof. Martin of UMass Lowell.

You can sign up to be a tester by completing the form at

http://tinyurl.com/aig-beta-request

Announcing: MIT App Inventor Open Beta Preview

hal — Sun, 04 Mar 2012 15:56:37 +0000

The MIT Center for Mobile Learning is delighted to announce that we’re meeting our goal of making MIT App Inventor available as a public service in the first quarter of 2012.

For the past two months, we have been conducting a closed test of the system for an increasing number of testers, and we’ve currently scaled to 5000 testers. Today, we’re taking the next step, and opening the MIT App Inventor service to everyone. All you will need is a Google ID for log-in (for example, a Gmail account).

App Inventor will now be suitable for any use, including running classes. But please be aware that this is the first time the system will be under load from a large number of users, so there may be bumps and adjustments as the load increases. For now, we suggest that you maintain backup copies of important apps, as we see how things go.

Of course, there are glitches and minor errors and lots of room for improvement. We’ll be turning our attention to these improvements, once we have more experience with running the system at scale. We will also be developing more resources and support for using App Inventor as a learning tool. We look forward to working with you over the coming months to build the community of App Inventor educators.

We owe a large debt to our testers of the past few months; it’s been their feedback that’s given us the confidence for today’s announcement. And we’re tremendously grateful to the folks who have been running their own system with the MIT JAR files. Their experiences have been an invaluable source of information, and their work has been critical in keeping App Inventor alive while the MIT service was not yet available. We also want to acknowledge the growing group of developers who are starting to explore the App Inventor source code. They are the seeds of an open source community that we hope will take App Inventor beyond anything we could do by ourselves at MIT. And our extreme gratitude and admiration goes to the Google App Inventor team who, even while their project transitions out of Google, have continued to share their expertise and the fruit of their hard work of the past three years.

Please join with us in helping the system move to its next phase as an MIT service. You can learn about MIT App Inventor by visiting our new home at http://appinventor.mit.edu.

MIT App Inventor mid-January status update

hal — Sat, 21 Jan 2012 17:00:06 +0000

It's been three months since we started work on App Inventor at the MIT Center for Mobile Learning and three weeks since Google's public service went offline. Here's brief progress report on the replacement public service we'll be deploying at MIT.

So far (knock on wood) our development effort is on track for releasing the MIT Public App Inventor Service in the first quarter of this year. While unexpected issues can always arise, we're guardedly optimistic that people who plan to run App Inventor courses or workshops can anticipate being able to use the MIT service by mid-April. But please check the postings at this site about the status of the public server before you make firm commitments. Remember that, as a backup, you can run your own App Inventor server using our JAR files as described below.

Here are some other developments and things we’re working on:

Some users of Google App Inventor didn't notice the warning that they would need to download their projects in order to preserve them after the shutdown of the Google service, and there have been several cries for help from distraught users. Though some last-minute heroics, the Google App Inventor team was able to package up everyone's projects and store them in a zip file in their Google Docs account. Google can't guarantee that all projects survived, but at least 95% of them did. So if you didn't download your projects in time, check your Docs files; and give some thanks to the Google team for making the extra effort to do this at a really busy time during the transition to MIT.

Here at MIT, testing with the MIT experimental service is going well. We've just admitted 300 more testers, making 700 testers in all, and there's a long waiting list. To get on the waiting list, read the information at Help test the MIT prototype service and fill out the form. We'll work through the waiting list as fast as the service becomes stable enough to handle the load. Our work at MIT over the past two weeks has focused on improving the “build server” that packages apps for the phone, and we'll be watching that carefully over the coming weeks as we add more testers.

Our Java Archive (JAR) distribution, which lets people set up their own small-scale App Inventor services, is also in good shape. There's a lot of use by individuals and also by classes: the JARs are our temporary solution for people who need to run classes before the MIT Public Service becomes available. One issue that has surfaced with the JARs is that, when there are more than a few students, App Inventor daily usage can out run Google App Engine's quota on free service. If you're in that situation, try turning on App Engine billing for a day and seeing how high your load is. People who have done that report that the App Engine cost turns out to be a couple of dollars per week, something that should be tolerable until the free MIT service comes online.

For developers and hobbyists, the big news this week is that Google has just released the App Inventor code as Free and Open Source Software, as described here. We hope to nurture a rich open-source community from MIT, but we won't start doing that until our public service is running. For now, we’ll leave it everyone is free to experiment with the code as they wish.

In summary, three weeks into our projected three-month transition period, we're on track. If we make our goal smoothly, it will be with enormous gratitude to Google: to Google Research for providing the funding to create the Center for Mobile Learning, and to the Google App Inventor Team for a simply monumental effort last fall to port App Inventor to the open-source implementation, that we are now finishing up.

Google and MIT announce open sourcing of the App Inventor code

hal — Sat, 21 Jan 2012 00:46:09 +0000

Google and MIT are pleased to announce the initial free and open-source release from Google of the App Inventor source code at http://code.google.com/p/app-inventor-releases/.

There's little supporting documentation yet, and we’re not accepting contributions to the code now. That will happen later, after the MIT Center of Mobile Learning opens their App Inventor server to the public. We hope to nurture a robust and active open-source project eventually, but for now we don't want to distract the MIT developers from their efforts to complete and deploy the large-scale public server. In the meantime, we’ll update the code periodically to match what’s running at the latest MIT experimental system. We've also created a Google Group here for people working with the code to relate their experiences with the code, ask questions, help each other, etc.

People who create modifications from this code base are free to use the term “App Inventor” and the puzzle-piece Android logo in their work. MIT will be releasing its own versions under the name “MIT App Inventor”, which is reserved for the systems actually coming from MIT.

Enjoy the code, and Happy Inventing!

Help test the MIT prototype App Inventor Service

hal — Tue, 06 Dec 2011 21:21:31 +0000

The Center for Mobile Learning is planning to deploy a public App Inventor service some time in the first quarter of 2012, to replace the service that Google will be turning off at the end of December. We've just launched an experimental prototype, and we're looking for people to help test the service. We'll start by opening the service to a small number of testers, and we'll add more testers as we gain experience over the next several weeks.

Keep in mind that this is an experimental prototype, not suitable for serious use like teaching classes in the interim period before the MIT service is formally released. For that kind of interim use, please see Running Your own App Inventor Service.

We expect the prototype service to be up and down without warning, and to be unreliable about saving user apps. If you can tolerate that kind of unreliability, we'd appreciate you helping us test. The better we test, the sooner we can make the new service publicly available.

To apply to be a tester, please fill out this form.

Development Starts at MIT

hal — Tue, 08 Nov 2011 23:06:27 +0000

I’m happy to use this first post in our App Inventor Development Blog to announce that MIT work on App Inventor is underway, and even happier to introduce Andrew McKinney as our newly hired technical lead for the Center and for App Inventor development. Andrew has a 20-year history of educational technology leadership at Harvard and MIT, including being lead developer on MIT’s Technology Enabled Active Learning (TEAL) physics project, which was MIT’s signature redesign of our freshman physics courses. You’ll be hearing from Andrew in subsequent postings to this blog.

Right now, our top development priority at the Center is to build an App Inventor service for general public access. This will be similar to the one Google currently runs and is planning to take offline at the end the year as announced last summer on the App Inventor Announcement Forum.

We do not expect our new Center service to be running in time for App Inventor users to make an uninterrupted transition from Google’s system to ours. Given the amount of development and testing required, the best we can say now is that we plan for it to be available sometime in the first quarter of 2012. We regret that this will disrupt plans of educators who anticipated using a public App Inventor service in January and February.

Even though our general public service will not be ready, we’re working to make it possible for technically experienced people to install their own small-scale App Inventor services to use next semester. For example,

Teachers and professors might deploy an App Inventor service for students in their classes.
School IT departments might deploy an App Inventor service for some students in their school.
Computer hobbyists might deploy an App Inventor service for their private use or for sharing with friends.

These services will run on Google App Engine for Java. In order to deploy the service, you’ll need to be able to use App Engine for Java, or find someone who can run the service for you. We’ve just begun testing this code at MIT, and we’re aiming to make experimental versions publicly available before the end of December. A caution: These initial releases may be unstable, and we have not done load testing. So don’t rely on the initial service to support more than a few users. We’ll post more information as our testing proceeds.

Remember that in order to migrate your current App Inventor projects to these new services (your own, or our public one when it becomes available) you’ll need to download your projects from the Google server before it goes offline on Dec. 31 and save them to be later uploaded to the new service.