Mi Speaks

Mi Speaks lets you listen and read along to various media on your devices.
Key Features:
+ Listen using any voice on your device, download more in the Settings App
+ Import Text from other apps including from images and pdf files.
+ Background playback and pause
+ Highlight and follow spoken words.
+ In App Helpful tips
+ Offline Compatible
Premium Features:
* Unlimited Text Input
* Saved Speeches and Playback Positions
* Share spoken text as an audio file
* Increased Playback Speed with Turbo
Premium is available via In-App Purchases in the form of Monthly, Yearly Subscriptions or a Lifetime Purchase.
This uses Apple's Standard Terms of Use (EULA): 
https://www.apple.com/legal/internet-services/itunes/dev/stdeula/