Garageband is still the best value in my opinion. Look at how simple it is to copy and paste loops from other apps into Garageband.
What’s New in Version 1.3
• Create custom ringtones and alerts for your iPhone, iPad, or iPod touch*
• Import songs from the Music library on your iOS device
• Play or record with GarageBand in the background while using other apps**
• Addresses a number of minor issues related to overall performance and stability
* Requires iOS 6 or later
** Requires iPhone 4S, iPad 2 or later
Garageband is available for $4.99 https://ipadloops.com/garageband/