Category Archives: General

Google expected to introduce new Java compiler

The upcoming Jack & Jill compilers in Android | Saikoa.

Most Android apps are written in the Java programming language. Google’s Android software development system converts “source code” (a text file) written in Java, into the code that runs on the Android device.

In many programming language systems, source code is converted into the “machine instructions” of the processor. The processor does not speak “Java” but speaks its own language. A program called a “compiler” converts the original program source code into the “machine language” of the processor.

Many programs for Windows, for example, have been converted into the individual instructions that are processed by an Intel or AMD processor. The “compiler” converts the program source code into a .exe file that contains the machine language instructions of the Intel and AMD processor.

But what if you wanted your program to run on a hardware device that has a Qualcomm or ARM processor?

Continue reading Google expected to introduce new Java compiler

What are the hot programming languages for today

Here is an easy to read report on which programming languages are now “hot” in the market for software developers: Don’t Rely On Salary Data To Pick A Programming Language To Learn – ReadWrite.

The pace of change in software development is rapid – popular languages today may already be fading.  Pay scales for some niche languages are very high (such as Ruby)- but the market opportunity might not be large or lengthy.

Web applications and mobile applications are the “hot” categories. Within those categories, there are a variety of currently popular software development tools:

Continue reading What are the hot programming languages for today

Facebook followers: Click on “Get Notifications” to stay up to date

Thank you to those that are following these updates via Facebook.

Facebook tries to automatically figure out what posts you read. But if you do not “like”, “click on”, share or comment on pages that you have “Liked”, Facebook removes those pages from your daily “newsfeed”!  And that means pages like the App Inventor 2 Tutorial gradually disappear from your FB newsfeed!

There are two ways to fix this defect in Facebook.

1.  To insure that updates are posted to your newsfeed, click on “Like” on the App Inventor 2 FB page and then click on “Get Notifications” in the drop down menu:


You can change this setting at any time by visiting the App Inventor 2 page.

Continue reading Facebook followers: Click on “Get Notifications” to stay up to date

App Inventor Tutorial ebook now also available from Nook Books + others

You can support this tutorial effort by purchasing a copy of the e-book from any of the following e-book vendors – thank you for your help!

Sorry for the “spam” – this is to update the earlier post with the news that the ebook is now available from Nook Press. It took longer than expected for that version of the book to go live.

Just USD $2.99! Instant e-book delivery!

Available from


App Inventor Tutorial e-book now available from Google Play Books, Apple Books, Amazon, Kobo and Nook Books

My App Inventor 2: Tutorial e-book – the fast and easy way to create Android apps – is now available from Amazon, Google Play Books, Apple Books via iTunes, and Kobo! And its very inexpensive – less than USD $3.00! Less than a latte!

Read it anyway you want!

Read on the e-book on the Kindle or Amazon Fire, read on Kindle for Android free apps,  read on your PC or Mac, reading using the Google Play Books app on your phone or tablet, read on iPads or Mac OS X, or the Kobo reader software (all platforms!

Depending on the vendor, you may download a free sample!



  Google Play Books


Apple Books via the iTunes Store: App Inventor 2 Tutorial – Edward Mitchell


Kobo Books


Nook Books


Minor change to the web site

I have made a minor change to how posts now appear on this web site. Longer posts – especially the tutorial type posts – will show only their introductory text and images. Click on the “Continue reading–” link that appears below the post to read the full text.

By shortening the text that appears on the main page, page loads will be faster. Plus, more “short posts” can appear on the main page, making it easier to review recent content, quickly.

This change also creates a more accurate count of the posts that readers find interesting, helping to to identify the type of tutorials and content that readers want to see. Previously, full length posts, read on the main page, were not counted on the popular posts list.

Within about 2 months of starting to ramp up content on this web site, we are now seeing about 200 unique visitors each day, many arriving after searching for “how to” information using Google or other web search.

Please share these posts with your friends, using the easy social media sharing buttons that appear at the bottom of every post. Like us on Facebook, Google+ and Twitter or follow the RSS feed. Thanks!

An Update on the Tip Calculator App, and How to share on social media

I have added buttons after each post on the App Inventor Tutorial so you can quickly share these posts on Facebook, Twitter, Google+ and so on. Please feel free to share! Your friends might like to know how they can create their own Android apps too (unless they are stuck using an iPhone … oh dear!)

An Update on the Tip Calculator App

I said there would be 3 versions and I was going to publish version 3 this evening … but we ate at a restaurant tonight and I used version 3 to calculate the tip and promptly thought of improvements!

So this evening I rewrote Version 3 (whose tutorial will appear shortly) and then created two more versions!

  • Version 3 will introduce a refined user interface that eliminates user data entry errors completely.
  • Version 4 introduces “procedures” to clean up the code in preparation for version 5 and introduces the concept of “refactoring” where we rewrite the code to make it better.
  • Version 5 revises Version 4 to make the calculation of the tip fully automatic.

So scratch those previous references to three Tip Calculator versions – we are going for five!