Android: Last week, we discussed Circuit Playground for iOS, a comprehensive electronics reference manual. Android users can get in on the action with ElectroDroid, a collection of electronic reference information and tools available now in the Android Market.ElectroDroid offers a number of the same features as Circuit Playground, including resistor and inductor colour-code decoders, resistance and reactance calculators, voltage dividers and voltage drop calculators, and more. You can begin prototyping your circuit in the tool and calculate whether or not the end result will look the way you want, use the app's extensive reference guide to review the components you'll need, look up pin-out connectors and more.
If you're an Android user and you spend time at a workbench doing any kind of maker work, or if you just want to get started with your own DIY wiring and electronics projects, it's worth downloading. The app is free and ad-supported, but if you want to support the developer and remove the ads, the "donate" version is $2.69.