IK Multimedia is offering mobile users the chance to get iGrand Piano and iLectric Piano at a discounted price for a limited time. From October 15th through October 31st, 2013 you can get them for only $7.99/€6.99 each on the App Store. That's 60% off the normal price of $19.99/€17.99.
If you already have iGrand Piano Free for iPhone or iPad you can upgrade to the Full version at the special price through in-app purchase as well.
iGrand Piano includes 7 pianos with an eighth that can be unlocked when you register your app. 9 additional pianos are included in the Piano Expansion Pack through in-app purchase.
iLectric Piano includes 19 electric pianos, plus an additional 22 pianos available in the Electric Piano Expansion Pack through in-app purchase.