1. Notion
Notion is one of the most popular notation editing apps on App Store. Notion is a pro music app with very easy to use UI. If you are looking for the best music composing, editing and play back tool for your iPad or iPad, Notion is for you.2. Music Studio
Another great iOS app for musicians. Music studio is a desktop class full featured music production app for iPhone, iPad and iPod touch. You can save songs as WAV and AAC formats and share via AudioCopy, iTunes, Email, Dropbox and iCloud Drive.3. iReal Pro - MusicBook & PlayAlong
If you are looking for an easy to use but powerful music app for your iPhone and iPad, iReal Pro is for you. With iReal Pro, you can easily create, edit, print, share and collect chord charts of your favorite songs.4. Symphony Pro - Music Notation
If you are looking for a full-featured music notation app for your iPad or iPhone, Symphony Pro is for you. This is one of the most intuitive and convenient apps for your iPad Pro, iPad Air and iPhone. With this app, you can easily compose music, import a score via MusicXML, MXL, MIDI, or SP file from your Mac or PC and your cloud storage services like- Dropbox or iCloud. Symphony Pro allows you to export your score as PDFs, MusicXMLs, AAC, MIDI and Symphony file formats, you can also print your score with any AirPrint enabled printer, or share them using iCloud, Dropbox or via Mail app.