There is another big sale on Zondervan’s NIV Application Commentary series, with each of the ebooks selling at $4.99–on, among other places, Amazon. For the first time Zondervan is offering various discounted bundles, too. Check them out here.
As I’ve said before, I really liked Psalms vol. 1 in this series. There are a lot of really good volumes in NIVAC, like Genesis, Peter Enns’s Exodus, and the sleeper hit of the series: James (David P. Nystrom). (Seriously–I think it might be the best of the bunch.)
All the Table of Contents now are hyperlinked, so navigating via Kindle or iBooks should be relatively manageable. You won’t get the same sort of search power you’d get in Accordance or Logos, but the price is tough to beat.