Depending on what brand of smartphone or tablet you have, you may be limited to what eBook reading apps you have available and what formats they support. For Apple products, iTunes is usually the preferred option, since eBooks purchased there can be easily opened on the device. For Android devices, you can either visit a bookstore website and purchase the file from there, and then download the file to your device. or install a bookstore app like Barnes and Noble's Nook app, which will allow you to make in-app eBook purchases and allow you to read the book from there as well.
You can try using the Kindle app for downloading students books. Your local library may use a specific app for downloading books and if the book is being downloaded through them, you may have to inquire with them about the app they use for online reading.
the best ipod touch app for books would be ebooks you can find them on the apple website.
You cannot delete an app as it is downloading. You have to wait for it to finish downloading, and then you can delete it.
One of the best Android apps for downloading YouTube HD videos is Tube Mate. You can download it from Tubemate.com.
You cannot download an app that is in the progress of downloading. You must wait for the app to finish downloading before deleting it.
by downloading it
There's a free app you can download on your computer to read Kindle books. Just google "Kindle for PC"
A good video downloading app for an iPod 4G is aTube Catcher.
You can not delete an app while it is downloading. You must wait until it is finished. Be patient
The 'App Store' is for purchasing and downloading apps to your device.
By downloading it
It might be that the app is too big in size or that your internet is slow.