EveryonePiano is described as 'Use this application to simulate playing a piano on your PC keyboard and enjoy learning chores and the note layout using the available songs' and is an app in the Audio & Music category. There are seven alternatives to EveryonePiano for a variety of platforms, including Windows, iPhone, Mac, iPad and Android Tablet. The best alternative is Virtual MIDI Piano Keyboard, which is both free and Open Source. Other great apps like EveryonePiano are VirtualMIDISynth (Free), Perfect Piano (Free), Free Piano (Free, Open Source) and MidiKeys (Free).
Virtual MIDI Piano Keyboard is a MIDI events generator and receiver. It doesn't produce any sound by itself, but can be used to drive a MIDI synthesizer (either hardware or software, internal or external).
VirtualMIDISynth is a software MIDI synthesizer implemented as a Windows multimedia user driver, accessible as a standard MIDI Out device. It works on Windows XP (SP3) / Vista (SP1) / 7 (SP1) / 8 (both x86 and x64), and is based on the great BASS library from un4seen.
Perfect Piano is a smartphone app designed to teach players how to play and record piano songs of their own using their smartphone. There are many plugins to allow you to change the sound of the piano to things like a guitar, harp, and cello.
MidiKeys is a small application for Mac OS X that presents a miniature MIDI keyboard onscreen. You can use the computer keyboard to play MIDI notes, or click on the keys with the mouse. There is also an option to select a MIDI source and see incoming notes played on the keyboard.
IsoPad is the free Windows touch MIDI keyboard. It contains three different keyboard layouts. One of them is the familiar piano fingerboard. However, the others are way more suitable for modern touch interfaces.