Apps Source for my application

Over the summer I've dedicated a good chunk of my time to learning the basics of Android development. Through that I created an application called "555 Calculator". For those of you who don't know what the NE555 is, it's a chip designed to produce a square wave at a given frequency; the frequency is determined by the value of two resistors and a capacitor that are wired to the chip. Normally the process for figuring the values is a headache inducing trial-and-error process until you can come up with values that came as close to the frequency you wanted. This just does the hard work for you.

Digressing, now that the application has been developed to my liking, and I feel like there is nothing I can add to it that will aid in my learning, I've decided to release the source in hopes that others will be able to learn from what I've built. It covers a lot of the basics of any programming language.

Some of those things are, but not limited to:

-Simple "back" button implementation
-Read/write arrays to and from text files
-Loops
-Switch statements
-Name Value Pairs
-Sending data to a PHP script using JSON
-Receiving data from a PHP script using JSON
-Spinners
-Context Menu
-ADMob
-Toasts
-Bubble sort

I've included the source for both the application itself and the php script it communicates with.

The code is messy, duct tape and bubble gum messy, but it works and takes a real genius to crash it. Hope some of you can learn some things and save yourself potential hours of combing the Internet trying to solve the simplest of problems.

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