Forget hunting for a tape measure or a protractor. Use your Android phone camera and sensors to handle different types of measurements easily.

Handheld light meters used to be a photography staple, but as cameras with built-in light meters became both more prevalent and reliable, these devices became increasingly obsolete for everyday use.

Within each content area, there are one or more tutorials. Each tutorial consists of lessons. Each lesson should be a page detailing the concept being taught, along with sample code. Lesson and page ...