SQLite3 database per customer

Scenario:

Building a commercial app consisting in an RESTful backend with symfony2 and a frontend in AngularJS

• This app will never be used by many customers (if I get to sell 100 that would be fantastic. Hopefully much more, but in any case will be massive)

• I want to have a multi tenant structure for the database with one schema per customer (they store sensitive information for their customers)

• I'm aware of problem when updating schemas but I will have to live with it.

• Today I have a MySQL demo database that I will clone each time a new customer purchase the app.

• There is no relationship between my customers, so I don't need to communicate with multiple shards for any query

• For one customer, they can be using the app from several devices at the time, but there won't be massive write operations in the db

My question

Trying to set some functional tests for the backend API I read about having a dedicated sqlite database for loading testing data, which seems to be good idea.

However I wonder if it's also a good idea to switch from MySQL to SQLite3 database as my main database support for the application, and if it's a common practice to have one dedicated SQLite3 database PER CLIENT. I've never used SQLite and I have no idea if the process of updating a schema and replicate the changes in all the databases is done in the same way as for other RDBMS

Is this a correct scenario for SQLite? Any suggestion (aka tutorial) in how to achieve this?