Nope but if you want to watch the new releases as soon as they come out then you will need an account and then you will have to pay.
You can watch for free at Crunchyroll or opanime.
2 Week free-trials are completley free,But adding your credit card info is Needed
go to iphoneanime.net not only do they have naruto shippuden but they have bleach and a bunch of good anime and its all free enjoy
Crunchyroll was created in 2006-06.
crunchyroll or opanime
Crunchyroll offers a free tier that allows users to watch a limited selection of anime with ads. However, to access the full library, including simulcasts and ad-free viewing, users need to subscribe to a premium plan. Additionally, premium members can enjoy features like offline viewing and access to exclusive content.
Generally, Crunchyroll allows only one free trial per user for their Premium Membership. This means that if you've previously used a free trial with a specific email address or payment method, you won’t be able to sign up for another trial with the same credentials. However, if you create a new account with a different email address and payment method, you might be able to access another free trial. Always check Crunchyroll's current policies, as they can change over time.
you could watch anime in crunchyroll. just look for it in the appstore. don't worry, its free. :))
at crunchyroll http://www.crunchyroll.com/library/Eyeshield_21 but you must first log in to watch it.. but don't worry, it's free~ ^^
Crunchyroll removed it..T.T
Crunchyroll and Hulu both offer free and legal anime, with a wide selection.