Approach on how to store statistics data

I have a question regarding how to gather and store statistics data. First let me give you guys some background information:

Our company is creating a sales tool , which will be used on an iPad. One of the requirements is that we can track how the application is used by its users. So we want to know which page on the application is used, and also for how long. Our current approach exists of sending the data to a server, which stores it in a MySQL database to be interpreted later on.

My question is: how can we effectively store said data in the database? The amount of data needs to be as small as possible, but we have to be able to generate charts from it. Are there any best practices I 开发者_开发知识库should be aware of?

Thanks!

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I would suggest using a lightweight database like sqlite3, and store the data on the device. Sync it every so often, preferable at idle moments with wifi near or something. I don't know what your data looks like, but take a look at document-orientated databases too, maybe that will give you a more efficient model and prevent a lot of null fields.