Stephen Visser on scriptogr.am. I've had a chance to use several different BaaS services; (some may not fit exactly into that category) I thought I would write down a few of my thoughts. While GAE has many cool features (Mapreduce, Channel API, Python / Java, Task Queues, Cron jobs, NDB, etc), the flexibility and power is diminished by poor documentation and a mutineer community.
I'm not sure why so many people are jumping ship, but their recent changes in pricing and litany of features still in beta after 4 years of development may be contributing factors. It also straddles the line between being customizeable end-to-end and oddly constraining. Take for example Apple Push Notifications. In my experience, GAE doesn't offer enough off-the-shelf backend features (APNs integration, built-in REST api) to merit the compromise of features that other, more low-level IaaS services would be capable of.
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