I am writing an iPhone app, that requires cloud back-end DB storage. I have a couple options in mind, and was wondering which one is better fit?
What I need:
be able to perform GRUD in the cloud from the iPhone app
the DB needs to scale (speed-wise) without much or any management
schema free
all i need is to store maybe 1 million records
Google App Engine:
Uses bigTable, scales, and schema free, but I need to write a RESTful interface
CouchDB:
Recently released iOS support, RESTful built-in, but I worry about scaling when syncing with remote server
SimpleDB: (seems to be my best pick)
Has iOS SDK, so I can do GRUD directly, auto scale (I probably won't be running into the 10GB limit), schema free
MongoDB:
Don't know much about, from what I hear, it's faster than SimpleDB, and easy to setup, but again I need to do the admin work
Cassandra:
Too much work, for what I need.
Any insight or feedback or correction is great appreciated.
Regards,
Johnny