Many music schools that teach piano are very particular about learning to play on a "real" piano. They expect anyone learning piano to use a full-size, weighted, 88-key, recently tuned acoustic piano. Fortunately many digital pianos have been accepted by a growing number of schools as a respectable stand-in for practicing at home. This is due to the fact that many now have replicated the physical feedback one would expect when hitting on the keys of a real acoustic piano.
One would think that this rules out the iPad as a learning tool for piano lessons. While there are many apps that feature a virtual set of keys that you can try to play, there are other apps that can work with your digital piano and help you learn to read music, identify notes by ear, and even make learning more fun. Here's how:
MIDI in, audio out
Apple USB Camera Kit - The easiest way to connect an iPad to a digital piano is through the piano's MIDI interface. The Lightning to USB Camera Adapter for $29 can be used to connect your iPad to the MIDI interface of a digital piano. You will need to use an additional USB cable to attach to both the digital piano and the camera adapter. For older iOS devices with a 30-pin adapter, you can use the Apple iPad Camera Connection Kit also for $29. Once connected, any app that uses CoreMIDI on iOS should detect the digital piano instantly.
IK Multimedia iRig - Not all digital pianos have a USB style MIDI interface to connect to. There are two different products from IK Multimedia that you can use to connect to the 5-pin DIN connection on your digital piano. The iRig MIDI works exclusively with older iOS devices that have the 30-pin connector and costs $69.99. The iRig PRO can connect to your older iOS devices with its 30-pin adapter, as well as newer iOS devices have a lightning connector and even your Mac via USB. The iRig PRO can do much more than just connect to the MIDI interface of a digital piano and therefore costs $149.99.
Headphone Audio Out - After you connect your digital piano to your iPad, you can utilize a number of different apps like GarageBand, iGrand Piano, and iLectric Piano to enhance and synthesize the notes as you play them. The problem is that the music plays back through the iPad's built-in speakers. Consider attaching studio monitor speakers to your iPad like a pair of M-Audio Studiophile or KRK Rokits starting at $79 going up to $499. This setup will make even the cheapest digital piano sound absolutely amazing.
Bluetooth Airturn - Another great accessory that works well with many of the available sheet music apps (mentioned below) is a Bluetooth page turner. The BT–105 Bluetooth Wireless Page Turner for $119 is a foot pedal that connects wirelessly to your iPad as a Bluetooth device and will advance the pages of your music notes with each toe tap. This is a great way to keep both hands on the keys without having to worry about breaking tempo.
Learning to read music
Piano Dust Buster (Free Universal) - Geared more towards a younger student, Piano Dust Buster has two modes that it can listen to the music you are playing back, ether through the microphone or through the MIDI interface. The notes for the songs can be displayed in staff mode, which helps in learning how to read traditional sheet music. While the app is free and you start out with a handful of sample songs to learn, you can purchase additional song packs based on your skill level via in app purchases.
Piano Tutor for iPad ($2.99 Universal) - Also with built-in support for MIDI keyboards, Piano Tutor takes a more traditional approach to learning to read music. There are four different learning modes that will teach you how to read sheet music, practice your rhythm as well as a pitch recognition and song playback mode.
Piano Notes Pro ($2.99 iPad) - Like Piano Tutor, Piano Notes Pro has a MIDI interface and teaches from a more traditional sheet music approach. Hitting a key on your digital piano will show you its location on the sheet music as well as display its pitch name. This makes it a great utility to create your own musical score. In-app achievements let you know which notes you have mastered, and which notes you need to practice. There are even quizzes that challenge your understanding of music.
Better Ears for iPad ($14.99 iPad) In order to play music you first have to know how to listen to music. It is one thing to be told that you are off tempo, but if you do not know what having good tempo sounds like, how are you going to improve? There are ten different exercises included with Better Ears that will help you learn how to listen to music. Your progress will be tracked and when relevant, the app will link you to articles on Wikipedia that explain the concept being taught in more detail.
Managing sheet music
Steinway Etude (Free iPad) - Once you get more familiar with reading musical notations on a staff, you will want to grow your library of songs you have on hand to practice with. With an interface similar to the original iBooks on iOS, Steinway Etude has a library of sheet music as well as an online store where you can purchase additional music. There is even a 'top paid' and a 'top free' scores list. Steinway Etude, and all of the other sheet music apps mentioned here, works with the bluetooth Airturn page advancing pedal mentioned earlier.
Musicnotes Sheet Music Viewer (Free Universal) - Musicnotes.com is an online site where you can purchase digital copies of popular sheet music. Their iPad app can log into your account and download all of your purchased musical scores. You can also enable the feature to add your own musical scores in PDF form to your sheet music library through an in app purchase. There is a limited collection of different classical and holiday scores to purchase directly from within the app. What sets it apart from Etude is that you can annotate and add notes to your sheet music.
iClassicalScores ($1.99 Universal) - With an opposite approach to Musicnotes, iClassicalScores allows you to add your own PDF music for free but charges for the ability to make annotations to your sheet music. It does have the ability to scan in sheet music just like popular document scanning apps using iPad's built-in camera. iClassicalScores will also search online for freely available music scores that you can add to your library. Once you create your sheet music library, iClassicalScores will sync all of your music scores to your other iOS devices via iCloud.
NextPage for iPad ($4.99 iPad) - Managing imported PDF music files is what NextPage is all about. Linking to your Dropbox account, NextPage manages your personal sheet music library in the cloud. It will also allow you to annotate your music files and even create set lists. There is an accompanying iBook that walks you through the steps to scan in your paper based sheet music and create a decent looking PDF version.