I've noticed that for their YA series they've heavily discounted the first book when there's a sequel or new book coming out.
Right now
Die For Me is at $1.99. A few weeks ago
The Body Finder was at $2.99 and on the 15th they are releasing
Starcrossed for $0.99.
Next week they are releasing
Hereafter by Tara Hudson for $0.99.
For the summer they have 10 teen books priced at $2.99:
http://www.epicreads.com/page/edeals/