Self-Publishing Platforms Ranking

In terms of user-friendliness, speed of updates, features, support, and ease of use, I rank these self-publishing platforms as follows in order of best to worst:

Google Play Books Partners

Kobo Writing Life

iTunes Connect

Barnes & Noble Press

Amazon Kindle Direct Publishing

Part of the reason Barnes & Noble and Amazon KDP both get last place is because of the process of trial and error in getting the print editions to look right. Barnes & Noble ranks above Amazon KDP because at least their cover creator shows precisely what the printing press will create, while Amazon's system does not.